I had a 2001 cherokee and had to replace the coil twice in a few years. They are known to fail. Dunno why Jeep switched to that for the last two years of the XJ. FYI, for those who have 00-01 models and experience misfires after starting up on a warmed-up engine, it's the notorious heat soak issue. There are some fixes that work and some do not. I vented my hood to allow the heat to escape when it's parked after driving. I also had a relay hooked to the electric fan that enabled it to run a few minutes after shut down to cool the engine bay. This corrected the dreaded heatsoak misfire. Just a heads up.

@diegosalazar5653

3 ай бұрын

It just happened to my 01 and I’m no car guy 😭

Okay, I have been a mechanic for 0ver 30yrs. I have watched some of your videos, and, would bring things to you for repair. Anyone can plug a scanner in and see the codes, then start replacing parts to no end but, you double check your self and the tools you use. Whenever I am going to replace an expensive part, I will check several different ways to make sure that is the bad part, so as to not be a parts changer. Good job! Your a great mechanic!

You know Eric you are one of the smartest troubleshooters I have watched. Usually I can be way ahead of a lot of mechs. But proving you are Polish was loosing your license one day before you got it back, burning the tires off with Dad's car. When I was a teen I broke the pickup transmission doing very similar stunts and he made me put another transmission for punishment. Taught me a bit and probably easier for me than him in his 50's.

I hardly ever comment to videos but Eric O is the most thorough mechanic I ever seen great JOB Only man I seen that takes pride in his work. The small details is what makes a true professional.

it's always a pleasure to watch your video. I own a shop and I actually watch your videos during lunch hour for fun.

@SouthMainAuto

7 жыл бұрын

Oh that's cool. Thanks!

Thanks for the video Mr. O! It's still helping people after several years. Polish engineering at its finest! I just replaced the coil rail in my 04 grand cherokee 4.0 with 230,000 mi I was getting a slight miss at idle that got worse over weeks and finally threw p0306. Plugs only had 6,000 miles on them but, number 6 had hairline cracks in the porcelain (which I think were caused by a bad coil). Replacing that plug made it better at idle but it still had a miss and was knocking when giving it gas while driving. While I wasn't 100 % sure it was the coils, I replaced the coil rail along with new plugs and now it seems to be good

@isaiahlopez8764

Жыл бұрын

i just did the same thing and i just got the code that cylinder 6 is misfire what else could it be?

Love those Jeeps and the 4.0l but the coil connector is a giant PITA. Thanks for the video Eric.

I had this happen to me this morning after heading to work, I will be looking to work on this tonight. Thanks for doing this video and giving good explanation of the procedures you did. I can give you some info on the low oil pressure. It's the head...if the head has the 0331 casting number on it then it has small hairline cracks between cylinder 3 and 4. In late 99-01 the 0331 head was used and then in 02 a different head was used.

Thank you for showing the world that there are legit techs out there mechanics whatever you wanna call him that do care and do the right thing and think about the customer at the same time plus I love your work and on a 2000 Cherokee is that's also what I own

had same issue in 99 xj, replaced both o2 sensors, replaced coil, replaced map and crankshaft sensors... the problem ended up being heat soak. I think I have replaced all critical components on xj, should be all good for next owner. Lol

just starting watching your videos about a month ago. have to say I love your attitude. with as stressful as this job is and the hours we put into it it's nice to see the chuckles and positive attitude you have. there really are some days I just want to change professions. keep up the awesome videos my man.

@heyitschinoable

8 жыл бұрын

Same here man

Eric, firstly, the Jeep hat is critical for this job because it lets the vehicle know that it ain't dealin' with no pedestrian. Secondly, it is a common practice by Jeep DIY'ers and professionals alike to avoid aftermarket electrical components on Jeeps. They report a higher failure rate with aftermarket and claim that OEM (mopar) components reduces "be backs". Your mileage may vary.

Nice work. Love the 4.0L power band but rough idle seems to inherent.

Excellence. Almost could imagine you were working on mine! Same year, color, 250,000 miles, cylinder and troubleshooting dead end after tune up done by previous owner. Had it 3 years now, love my jeep....301 slightly rough idle the last thing to dial in to move onto trustworty 4WD use and a throw a few dollars at cosmetics. Correct, simple and complete explanation....brief too, Subscribed and Thumps Up for sure.

Nice video. Six-pack coils. Probably saves the company 30 seconds when they're putting the engine together, but when it comes time to repair, the customer has to pay for six coils, instead of one.

@SouthMainAuto

9 жыл бұрын

Garth Goldberg Time is money for them right ?

@stanleynowak9325

6 жыл бұрын

One hundred bucks for six all new coils makes this engine idiot proof.

@nodak81

6 жыл бұрын

Three coils

@OldManBadly

5 жыл бұрын

3 coils (they use one for two cylinders) and replacing them as a block if they have failed isn't a terrible thing. When one goes like this, it's likely the rest are about as worn. So not a big deal, and honestly the price for the thing isn't horrible at all.

@GNX157

5 жыл бұрын

The 86 and 87 Grand National were the same way. The module was right under it. Back then this ignition style was quite advanced.

Thanks for making this video. I have a misfire on my 01 Cherokee and now Im sure its a bad CP. You saved me all those diagnostic tests

@SouthMainAuto

8 жыл бұрын

+John Gluse cool glad it helped

Recently swapped one of these 4.0s out of an xj with 265k. Remember when they had distributors on them? The good old days. Sweet videos man. Good work

@8avexp

4 жыл бұрын

My '88 still has a distributor.

@Deadbuck73

2 жыл бұрын

My 99 just got a new cap and rotor… 246k.

A coil pack. My Wife's 97 Grand Cherokee was a 4.0 L, with wires, cap, rotor, & coil. Easy. Pontiac had a 4 cylinder that used coils on top of plastic with internal connections that sat on the spark plugs at the top of the engine. The misfire was an internal short in the plastic between coils. Lucky only the plastic needed replacing. That was back in the mid 90's we fixed that.

Of course on your spare time, keep up the honest work and videos of your repairs.

Great video, I have a 2000 cherokee as well with the exact problem, I verified it was the coil... so I just picked up a good coil at the junk yard for 50$, will be putting it in tomorrow.

Thank you! I never new how easy this fix could be and you showed me what I was missing when trying to fix my Jeep! 5:00

Best mech videos on U TUBE - and from a HONEST mechanic - a VERY RARE combination! You're the best!

i watch many auto tech videos and i think yours are some of the best !!! very informative and your video skills are great

@SouthMainAuto

9 жыл бұрын

zoie godwin Thanks :)

He'll be back come inspection time. Thanks for the video.

a simple test to determine if the misfire is electronic or mechanical is hooking up a vacuum gauge. pretty quick way to determine what you should be chasing.

Nicely done Eric and thanks for bringing us along.

@SouthMainAuto

9 жыл бұрын

stuzman52 Hey Terry, Thanks for watching :)

South Main Auto Repair, thank you for posting this video. I followed your video and swapped out my ignition coil and 2 weeks later no issues. You helped me out of a tight spot. Only thing, taking out mine was very hard and I actually broke it during removal. I appreciate all you do.

great job Eric just did a Grand Jeep 8 cyl CPS was out acted like starter drag kept shutting off after crank that did fix the problem ... I never seen coil pack like that though glad you got a fix .... have a great day! ;)

I had that 'Six" in a Grand Cherokee (1996) with the 'low oil pressure'. Replaced the oil pressure sender and oil pressure was good as new.

@philmerrifield1163

3 жыл бұрын

Half the time time, they ain't very potty trained. Last jeep I had, used to piss oil EVERYWHERE 🤣

Another great informative video. So far I have watched all of your video's. Btw I called you a few weeks ago about my ex's 2009 Chevy Impala. It had that po401 code. Well I did what you recommended and it worked. I replaced the secondary air injection valve and the code went away. Thank you for the help and thank you for the great video's. When I get a chance I will make the drive up from Buffalo and come visit. Take care and thanks again.

@SouthMainAuto

9 жыл бұрын

Gregory Feeney Nice... I am a good guesser then haha

You taught me a ton in just 15 minutes. Thanks man.

@marcusjnewtonz28

5 жыл бұрын

Just as a follow up, after I got the coil pack back on I now have the part time light going on/off. And the check engine light flashing on/off. Neither ever happened before I took the coil pack off, would that have anything to do with the electric plug I plugged (by #6) back in? Maybe plugged in wrong? Seems like such a weird light to be getting. Any help is appreciated thanks!

Didn't know the 6 had oil pressure problems, everyone always says how great and reliable they are I have a 96 5.2 with143k and runs great, oil consumption and smooth as glass

@kipvevea5731

2 жыл бұрын

the oil pressure sending unit is prone to fail. I would change that before tearing into the engine

I figured that there was a dead cylinder due to spark because you said that the check engine light was flashing. The check engine light flashes because the catalytic converter is in danger of being destroyed. Raw fuel can overheat a cat and damage it. So if you see a check engine light flashing more likely than not this is the case.

@tjr9175

5 жыл бұрын

A consistent misfire will always cause a flashing cel light

I just started watching your videos. They are great. Wish you were closer.

Glad you had a nice easy quick fix. I left work with a sore ass from an 05 tribute p0750. Solenoid functions when commanded, fluid is good, ppppfffffffffff!!!!!!!!! I'm surprised you don't have a custom camouflage SMAR hat. Thanks for the video, looking toward to the next one.

@SouthMainAuto

9 жыл бұрын

Michael Herbert Dang, get those once in a while that wanna beat you up a little:)

Awesome video, Great information... Thanks for the help.. God Bless you ❗✌❗💪❗

Thanks man! Great video! Appreciate you taking the time to share your knowledge

Thanks for showing us how to do it! Now, roll in bearings, pull the head and get a valve job, ball hone the cylinders and install some sealed power pistons and new cam and lifters only if needed, add timing set, already have new oil pump, in under $500 Will restore compression and maybe some oil pressure will run like new for years easy, keep running rotella, they need it anyway for the cam Or spend another $1000 and build a 4.6

@hectorflores3808

3 жыл бұрын

Stroker is the way to go

We have a lot of your relations here in Galway,lovely people and great workers.Liked the video.

@SouthMainAuto

9 жыл бұрын

Tom OConnor Oh really? People with my last name?

@spelunkerd

6 жыл бұрын

Tom, I didn't know you are from Galway, one of the most unforgettably beautiful places I've ever been. The whole of Ireland is amazing.

There is nothing better than a straight six.

You keep teasing us with those shirts! Lol. Always nice to have a quick and easy job once in a while.

@SouthMainAuto

9 жыл бұрын

Jonathan Milbury Soon :)

As the owner of a 2000, 1998, and 2001 Jeep Cherokee and previous owner of several other Chrysler vehicles, I have never once put those stupid red locks back in any harness connector other than the fuel pump.

same issue 2000 Jeep Grand Cherokee Misfire only on cylinder 6 changed plugs oil coil and ran injector cleaner.No vaccume leaks.Car runs great for about 100 miles.Engine light flashes at high rpms and then misfires.Compression is all good.Not sure what the issue is haven't replaced or tested the injector yet

Awesome video man. I learned a great deal of info to help get rid of this stumbling. Thanks man! 🍺

I know this jeep is long gone, but on the 4 liters they have a problem with sludge buildup in the oil galley behind the pressure sensor causing a low reading. Might help you out sometime in the future.

good repair well done Mr. ERIC and thanks for sharing.

@SouthMainAuto

9 жыл бұрын

j georges YW

I love your videos man quite a bit different than a lot of other channels but you never disappoint with a video haha keep up the good videos and proper work

Very methodical diagnosis. Well done.

Great Video man....pretty straight forward and great explaining along the way. No carrying on about stupid shit. Thanks.

my 97 GCL pulled up P0300,305,306. also codes for the coil, O2 sensor. I replaced NOTHING but the CRANK POSITION SENSOR and all problems were solved. There's a cheap Lil piece of felt on it that erodes over time....

i just bought a 1998 Jeep grand cherokee 4.0.,it idles rough,but runs smooth as soon as you mash on the gas,it runs smooth,i cleaned and re-gapped spark plugs and distributor,i'm starting to think it's the distributor pick-up coil.

got to love quick and easy after that long hard winter.

@SouthMainAuto

9 жыл бұрын

super coupe Oh for sure...

There is a chance the O2 sensor problem was a result of the misfire, Good fix!

I had this exact same problem. O2 sensor and all

I have a 02 Dakota 3.9l check engine light came on p0306 running rough backfiring/ misfire watched this video I hope it’s the same exact thing on my truck

Jeep grew out of American Motors Company. AMC joined Jeep. AMC went out of business. Then Jeep provailed. AMC was Ford, G.M., and Chrysler combined. Jeep grew away from Army Jeep style to Renegade and Minivans. On Renegades, the diagnostic port is in the engine compartment. On Minivans it's in the passenger compartment on the left side. Cars with deep well plug holes require deep well insert kits.

@rmxautomotiveltd.2846

5 жыл бұрын

Actually, AMC was Nash-Kelvinator and Hudson motors combined. It never included Ford, Chrysler or GM, though they used parts from all 3 in their own vehicles. Jeep was always a product line, not a mfr, originally owned by Willys and then passed down through Kaiser, AMC, Chrysler, and now (sadly) Fiat. AMC also spun off AM General around the time they went under, which mainly served military contracts, and still exists today. This is why the HMMV resembles a Jeep in many ways.

Nice quick diagnosis.

I got a ripp mods dodge viper coil pack on my 2000xj, it's the dodge viper style but aftermarket high output. It's got plug wires now so that's exciting lol

Love the video see this what I need a mechanic like you I trust u just watching this video I have blinking check engine gas smell going through my Exhaust I'm lost I smell gas on driver side not valve cover passenger side seems ok I haven't inspected anything I have to watch videos learn step at a time

i always find it funny when people say they have low oil pressure and think replacing the oil pump will fix it.....oil pressure is created from the engine clearances inside the engine..the oil pump is just there to pump oil to the engine for lubrication. great video as always, just though i would throw that in lol .

@SouthMainAuto

8 жыл бұрын

+Herschel Herndon Yep your right :)

@jeremyproctor9671

8 жыл бұрын

+Earl Guyton please step away from the keyboard go and gather up all your tools throw them in the river and NEVER touch anyone's vehicle again for the love of god

@SouthMainAuto

8 жыл бұрын

Jeremy Proctor ?

@jeremyproctor9671

8 жыл бұрын

+South Main Auto Repair i was just marveling at Earl Guyton comment everyone (i guess only us mechanics) know crank clearances is everything when it comes to having good oil pressure ruling out the oil isn't pure sludge

@SouthMainAuto

8 жыл бұрын

On 4.0's 90% of the time we find the cam bearings are wasted...

Good video! Thanks it helped me diagnose a misfire

Good job Mr. " O ".

Well done video, thanks for sharing

just a note anytime I need to know the companion cylinder take the firing order put the first half on top of the second half and you will have your companion cylinder.

@SouthMainAuto

9 жыл бұрын

Robert Young Yep every 720 we have a firing event so with the firing order you can figure it out pretty quick :)

have to say thanks, recieved the sma coffee cup, perfect to hold the java while checking out at your vids , thanks again

ok listen up I used to panic when my oil pressure in my 92 Cherokee dropped to around 20 from 40 psi tried Rislan, (still put it in can't hurt) thought it a jeep 4.0 L thing. years later got a 01 Cherokee. With the infamous 4.0L in it what can I say I like those things and guess what it does the same thing, changed the oil sending unit Rislan again, decided to consult the OWNERS MANUAL when I got one light bulb time. the pointer indicates engine oil pressure this gage does not indicate level readings are 20-60 in city driving and 45-60 at highway speeds, pressure varies with speed temp and oil viscosity, hot engine idle pressure of 13 psi is fine constant lower readings like accelerating and your pressure doesn't move above lower reading than you have problems but if it rises to the higher reading your fine, the last part is my own words cause that seems to be a Jeep 4.0L quark I'm not saying ignore it but keep an eyeball on it and you should be fine

Best video out of all 20 i seen! Great job bro!

Nice and easy Repair Simple Diag On this one Just a bad Coil good work Eric O was very Entertaining @SouthMainAutoRepairLLC

Love the Jeep vids. 👍

Well done Eric- Thanks

Its a good thing how you explain things as you go n your preety dam good at what you do thanks for the info n help

Just the way I like my cylinders, in a line! Whats telling him he has no oil pressure when it's hot? Without a mechanical gauge it's really just a guessing game. Another interesting video, thanks

@SouthMainAuto

9 жыл бұрын

Rick James Lol he has an aftermarket screwed to the dash... he didn't believe OE gauge so installed aftermarket :)

Thanks Eric great job !! Is it possible the paired cylinder with the #6 coil is still operable and not creating a misfire for the paired cylinder. Was it possible to do a OHM coil reading on the #6 and compare with others for a confirmation ? Thanks again, great video !!

I have never seen a coil pack like that. I bet it is expensive.

You don't need to check the dates on Ericsson videos just check the wear on the brim of his hat.

This was great, I learned so much! Thanks man.

Great video. If I can do it you can do it is inspiring. I Replace my PCM based on code but still skipping. Local mechnic thinks its the head gasket. going to see if its coding tomorrow

Quick and efficient diagnosis. If it's a coilpack and has a companion then why wasn't the companion misfiring? Wouldn't that make it more of a coil on plug setup if it could misfire individually?

@xerxes456

9 жыл бұрын

***** You could have a crack in the coil and it will take a short-cut through engine block to the other cylinder spark plug. current take the path with less resistance.

@halleffect1

9 жыл бұрын

***** surprisingly it doesn't always work that way. Scannerdanner has a video on this subject with an explanation. I don't remember which one.

@supercoupe6288

9 жыл бұрын

***** these coil packs have a copper ribbon that runs from the coil to the each companion cylinder, the ribbon to one of the cylinder could've shorted and the other would've keep firing

@DJDevon3

9 жыл бұрын

super coupe A ribbon is just asking for trouble no matter how well it's sealed. Even though the whole rail looks really neat and easy to work with I'm not a fan of the design if there's a ribbon. Round wires can help contain oxidation to outside layer in the even of a crack in the housing. A ribbon has a flat surface area that will corrode away pretty quick. Great info thank you for sharing that.

all jeep and dodge have oil pressure switch problem did he try one . Good job Eric

Problem with those name brand caps is that they don't keep sweat from running down into one's eyes.

i love the XJ

The Buick GN had this same style all in one. The GN community was quite large, and a vendor came up with a stand alone unit to test the coil packs far beyond what was available, and to simulate running the engine under high boost, which will put out all but the best ignition spark. Here's a video of the tester in action. You can see that they all work, but one begins to fail under heavy load. The GN Turbo motor needed everything top notch to perform as it should. kzread.info/dash/bejne/g2qFr8qug7msaLw.html

I like the RIpp coil pack conversion kit for 2000- 01 Cherokee it’s a high performance kit that is awesome “ it’s around 300 bucks

I had a 04 Chevy Silverado to diagnosis coolant sensor circuit high sensor was broken at connector on sensor side have to love road salt

@SouthMainAuto

9 жыл бұрын

Christopher Barone Ahhh salt, it's a thing of beauty :)

same thing happened to my 2005 chevy trailblazer 2 coil packs went bad while driving it sucked but it happens replaced them both after reading the codes cuz i knew already going into it that was most likely the problem trailblazers are known for it

Thank you for the video...helped me with my Saturn ls1. 😄👍

I keep forgetting to give you the thumbs up but I remember this time

My 99 has 411000 miles no oil pressure problems

@andrewevanoff1192

7 жыл бұрын

Mine is a 98 GC, same engine. No issues with the engine (or anything else) since I bought it brand new. Best vehicle I even had. Very tough and reliable. It still runs and looks like new. Can't say this about my 2010 Tacoma.

@landontesar3070

5 жыл бұрын

That is fantastic, please tell how you do it. Would like my '98 to last.

@alexandersimcox2079

4 жыл бұрын

@@landontesar3070 change the oil at the recommended intervals with high quality synthetic oil, and replace the filter with every oil change. Theres no magic goop you can put in the engine to make it last forever, just doing the maintenance will go a thousand times farther than any oil additive off the shelf at an auto parts store. If you're towing, offroading, or otherwise beating on it a bit more than the average driver, change the oil earlier than necessary. An oil change is under a hundred bucks even with top of the line fluid and filter, an engine is thousands and even more to have it installed. Dont neglect the coolant, transfer case, or differential fluids either, again, relatively cheap and easy to replace fluids at recommended intervals, but very expensive to replace components. Change manual transmission fluid regularly, DO NOT change automatic transmission fluid if it hasn't been done regularly since the vehicle is new, often the goop in the old fluid is what's keeping it all together, just top it off if it gets low. Short version: do maintenance.

@landontesar3070

4 жыл бұрын

@@alexandersimcox2079 Thanks, Alex. Just bought an old tractor, asked the seller, you change all the fluids? He just sort of looked at me. Hint: (that's a 'No') Oil was the worst I've seen since a toronado diesel, and think the water pump impeller has disintegrated. 5 gallons of 80W-90 is in the future.

Well done! I think the lucky cap helped on this one :)

@SouthMainAuto

9 жыл бұрын

***** Oh it sure did... special powers :)

you were right it's got coil packs it still got water in there .

Those Jeep XJ 97 up oil pressure gauges are inaccurate sometimes & read low or drop off. I replace the sender no improvement. I found I had perfect oil pressure when I put a mechanical oil pressure gauge on my Jeep. About 15 lbs difference.

I wonder why american manufacturers started with kind of coil near plug ignition. Glad they finally went with coil on plug though. I used to own a 94 bmw 325i that already had coil on plug.

@a89proof

5 жыл бұрын

Partially a slow transition from OHV to OHC cylinder head design, and maybe a need to just get a working system that would make it through emissions warranty without dealer service expenses. I'd guess Bosch might've developed the coil-on-plug design in conjunction with German auto makers, as my early 90s Asian and US stuff all had distributors, or plug wires to remote coils. GM cam in block LS engines are still using coil near plug and stubby wires.

Couldnt you just change the boots?

Good video, very helpful. Thanks.

That used to be Martin Yan's hook at the end of his cooking show - "If Yan can cook, so can you!"

@SouthMainAuto

9 жыл бұрын

hoppes9 Oh nice haha

wow I wish it was longer. I'm also having problems with my jeep as well, the car turns off when I drive at times it turns back on after a minute of waiting and starts working for a couple of minutes but does the same thing again. po351 ignition coil 1 is not good po300, po301, and po306 misfiring idk how exactly to fix it but ima try out what you did see if that helps it a little.

@tristaprice8315

5 жыл бұрын

Jeeps are also known for the cam and crank sensor going if it stalls while driving it's more than likely one of the 2 sensors....I had the same issue on my 95 Cherokee and it turned out to be both sensors couple days apart from each other.....

I was suspecting the cam had twisted , just past cyl #5. lol

@SouthMainAuto

9 жыл бұрын

wtbm123 Hey you never know when a cam is gonna get all messed up and twist on ya....

@heyitschinoable

8 жыл бұрын

+South Main Auto Repair VW just had a bunch of cars recalled at my work for possible cam lobes breaking off lol no really...

The rubber insulation around the coil pack connect is shart.

Just something I noticed in the diagnostics... The 'CYL6 MISFIRES' maxed out at 255. That's probably because of the old 8bit electronics - 255 is the biggest number you can count with 8 bits. If something reads 255 my guess is the actual number is bigger and growing. Not sure - but makes sense to me;) """The largest number you can represent with 8 bits is 11111111, or 255"""

My '88 Jeep has one coil and a classic distributor.