2000 Trooper engine problems

Hi all,
About my 2000 Trooper, it started about 2 weeks ago, I drove my wifes Trooper and noticed it was running rough. I added an injector cleaner, 2 days after that the CEL came on. Found your forum and followed advice from many posts...cleaned EGR and PCV, which seemed to work for awhile but it always went back to running rough. Went to Autozone and got these codes:
p1290, p0171, p0174, p0175, p1340 (2X), p0300 (2X)
Fuel metering, too lean, too rich, and misfires. Went to check the spark plugs but can't get the boots out of the head and at over $100 each I can't afford new coils if/when I tear them up (can I take the valve covers off to get to the spark plugs?) So I changed the intake manifold gaskets and the fuel filter last night (only two hours, not bad, huh?). It was running REAL bad before I changed the intake gaskets (passenger side was in 4 pieces), coughing, bucking, and missing and runs better now BUT it misses after running a couple of minutes, and gets worse the longer I drive it and has no power. The CEL blinks under any acceleration after the first couple of minutes, and you can feel it miss. I have cleaned the EGR valve several more times, but no change. Could the spark plugs cause this? Maybe the injector cleaner loosened something in the fuel line that cloged an injector? Any help will be greatly appreciated.

Thanks

How many miles?

What codes do you have after the changing the IMG?

Link to plug how to:
http://isuzufaq.ibctech.ca/#faq15

The key to get the coil and boots off (it is 2 peices, so don't freak when they come apart) is to twist, twist, twist and then twist and pull. Get your fingers under the coil and do this.

For real stuck coils ( I had one) I use a loop of string (see my gallery photos here).

You cleaned up the EGR and PVC which is good. But did you clean up the EGR port? It is behind the butterfly (see the FAQ for a how to).

Once you have the codes you may find out you have a bad coil. If you swap the coils around you pin point which coil is bad.

Also, with you recent injector cleaning you are correct that you could of freed up some junk. I know there was post here about a simular problem and the owner knocked on the fuel rail (while running with a wrench?) and the engine smoothed out.

A flashing CEL is bad news. It means that there is some serious missfireing ongoing and it is really hard on the Cats and O2's.

Steps forward:

1. Need the codes.
2. Try the knock on the fuel rail trick
3. clean the Egr port
4. Reset the ECU (pull the battery connections for 15 minutes).
5. clean up the battery body ground points (the ground point on the alt too).
6. change the plugs (see the faq's for the right plugs).


report back and We'll help get'er back on the road.

-Ryan

It has about 56000 miles, and haven't been back to Autozone, it'll probably have to wait till Saturday.

see the above (I was editing while you wrote again).

http://www.automotiveforums.com/vbulletin/showthread.php?t=359321&highlight=fuel+rail

here is the fuel rail thing.

You have been getting some EXCELLENT advice so far. I only have two additions.

As I understand your situation, when you remove the coil pack the boot stays in place. If the string tip doesn't work do you have a manual tire pump? If so I have read about using that to help pop the boot. You put the end over the boot and seal it with your free hand and give the pump a little push. Maybe a little duct tape or a nozzle tip like you would use to fill an air mattress may help seal the tube better and help it pop more easily??? Again just something I read that may or may not work.

Also, to help prevent this in the future, once you get them off you may want to add some dielectric grease to the plug top/tube bottom.

Have you ruled out all vacuum leaks at this point? Make sure you cannot hear or feel any vacuum leaks around the common chamber. Are they the original spark plugs? The reason I ask is, if you use anything other than denso spark plugs in a 2000+ 3.2/3.5 you will get random misfires and all sorts of problems. This could also be a mass air flow sensor issue, where a bad MAF is really messing with the fuel trim. The MAF comes into play more when the vehicle has come up to temp, which would make sense as you described it runs better when cold. Just some thoughts!
G/luck
Joel

OK, Cleaned the EGR port in the intake plenum, knocked on the fuel rail, reset the ECU by unhooking the battery for 15+ minutes. Sent my wife (she asked what she could do) to Autozone and they said come back tomorrow, BUT when I turned the engine over to move it into the garage...NO CEL!!! Still runs rough though, and after putting gas in (premium, to see if it would help) it started running better, so I went to the off ramp and floored it, and blinking CEL. But it runs a little better. Looks like plugs next? The ones in it are the originals. Also, what is a Mass Airflow Sensor and where is it? Can it be replaced? Expensive? After this I don't think I'll be timid about working on this thing anymore! And also, thanks a million for all the help! It is greatly appreciated. I have belonged to several VW Old Beetle forums in the past and no one has come close to this forum for useful and forthright information.
Thanks again,
Brett

are you the orginal owner? All gaskets (including the IMG) are covered for 10yr 120k first owner, and 6yr 60k second owner. If you come up with a code for a bad IMG let isuzu change it out on their dime.

If you are not the first owner then maybe the previous owner put bosch +4 plugs in (Isuzu's don't like these plugs).

The Mass air flow sensor is right next to the air filter.

good link on it:
http://isuzufaq.ibctech.ca/#faq62

A new one costs 150 bucks.

If you are running a K+N air filter the oil from it can coat the wires of the MAF.

It still sounds like a bad IMG. Did you torque em correctly right?

http://isuzufaq.ibctech.ca/#faq70

And yes, Isuzu owners are a unique bunch of people.

Photo of my Isuzu and my VW:

https://mywebspace.wisc.edu/rendres/web/1958/PICT0002.JPG

I am the original owner BUT on a trip to Missouri in the fall of '03, my wife seized the motor, you guessed it, no oil. No help from the factory either. We had to get a used one installed. I've rebuilt SEVERAL VW motors so I know the importance of correct torque values and tightening sequences, so I did it like it says, crisscross inner then outer, 16 ft. lbs., sneaked up on it about 3 times before I got to 16. I haven't checked it with water or carb cleaner AFTER I replaced them though, I will tomorrow. Maybe I can get Autozone to help with a reading too. I guess I don't really know what plugs are in it, but it ran fine for a year and a half on the ones in it. Can they start causing problems after that long?

Thanks,
Brett
P.S...Cool rims on the bug! Ragtop is cool too!

I would at least pull a plug (10 minute job) to see what it is and report back.

Brett, I wouldn't suspect the spark plugs if it ran fine with no CEL for 6 months, but you never know :uhoh: . I would look into the MAF first. Like Ryan says, its right up near the outlet of the airfilter box, clamped to the air intake hose. Do you know anyone with a late model isuzu? If you could swap MAF's with them for testing, that would be the best route. 2nd thing I'd check is make 100% sure you have no vac leaks.
G/luck!
Joel

Got the spark plugs out, the boots needed two complete turns to get out! The plugs are Denso, and brown, and electrodes are in good shape. I took out the MAF and wiped the back part out, it looked dusty, DID NOT GET NEAR TINY WIRES! Blew out the front screen with compressed air ( can it be cleaned better?). Put it back in and drove three blocks to get my kids, no change. This morning when I was checking the spark plugs I realized I did not hook MAF plug back in, did that and runs better. Still not perfect, stumbles off idle and at constant speed and part throttle on the highway. BUT it shifts better and I can get it to downshift without putting the throttle to the floor. Read a post about putting Techron injector cleaner in, and have had that product recomended to me, so I put some of that in. After I drive it I will report back.

Thanks again for the help,
Brett

I would plug the MAF back in and get the codes read.

another good post:


http://forum.planetisuzoo.com/viewtopic.php?t=3324&;

I plugged the MAF back in as soon as I saw it loose, The codes are:
P0102- MAF frequency low, P0300-Misfire
After Autozone we had lunch, during which I unplugged the battery to reset the codes, then went to run some errands ( city and highway) to see if the CEL comes back on or blinks...so far so good, no lights, blinking or otherwise. Still runs rough. Tried the carb cleaner around the intake manifold but nothing changed.

Still hoping for a fix,
Brett

ALSO...My wife reminded me, the catalytic converter started rattling a while back, could these be related?

Brett

Yes you can clean the MAF sensor. Use a Q-tip, alcohol and a very gentle touch. If you skip the last part you will be replacing the sensor.

Some of your orignal rich/lean codes could have been caused by a bad cat. But since you haven't touched the cat and you are not presently getting those codes I doubt it.

Did you tap the fuel rail with the vehicle running? If not then try that again.

In that we are moving on to other causes, you might check for a fuel pressure issue. If an individual injector has a problem those tend to flash a cylinder specific code. In that you are not getting that maybe you have a low fuel pressure problem (plugged filer, bad regulator, bad pump).

What do you mean by running rough? Surging rpms? No power? Harsh shifting? Only under load? At idle? Etc. Point being a more in depth current status report now may help

Idles OK in Park, Idles rough in Drive. When first starting in the morning or after sitting for 6-8 hours it runs good, shifts good throught he gears, but after 2-3 minutes, when the temp gauge moves up, it starts running rough under part throttle acceleration. If it was an old aircooled beetle I would say it has a hole in the accelerator pump diaphram or timing was off. Sounds like this: MMMMMMMMMM papapapapapapapapa, (MMM being running normal and papapapa being running rough). It does this when moving the thottle pedal down just a little and stops when let up. Also sometimes it hiccups, feels like it just quits then catches back up at cruising speed on the highway or under acceleration. Come to think of it, I had an old beetle that had a kink in the fuel line that acted like this. That's what makes me think a clogged injector or injectors. I have aleady replaced the fuel filter. I'll clean the MAF with alcohol today and report back. Can the injectors be taken out and cleaned? Or would it be better to buy one and shuffle it around to see if one is bad?

Thanks again,
Brett

.....Some of your orignal rich/lean codes could have been caused by a bad cat. But since you haven't touched the cat and you are not presently getting those codes I doubt it....

I don't follow this statement (not to say it's wrong! :thumbsup: ). I've seen a clogged cat not allow an engine to reach higher RPM's due to the fact that the engine can no longer pump it's normal volume of air. I've never seen a cat affect fuel trim. You will get a OBDII code from one of the O2 sensors downstream of a cat (sensor 2's) if the cat was at fault. I do know that running a 1998+ isuzu with a misfire and/or rich condition will sour the catalyst in the catalytic converters in short order. They will then stop processing hydrocarbons as they should & set off "sensor 2 O2 sensor codes.
G/luck
Joel

I guess we are even as I don't understand all of what you are saying. Like you so politely noted I am not saying you are wrong just I don't follow you.

I understand and acknowledge that I could have phrased the referenced quote better. Namely, "If you have a bad cat you still have the same bad cat. Thus, the codes that went away are not likely cat related."


"I've never seen a cat affect fuel trim. You will get a OBDII code from one of the O2 sensors downstream of a cat." Now maybe you can clarify this quote of yours. He did have O2 sensor CELS. They could have been caused by bad O2 sensors, engine problems, or cat problems. No matter the cause, the computer will cycle fuel settings to try and get the oxygen readings within spec. Thus, a bad cat can lead to fuel trim (rich/lean) adjustments. At least that is my take. I welcome your feedback.

Now whether he has a plugged cat causing the last 2 codes is another question. The low speed symptoms sound like this is possible. However he is not reporting limited power at high speeds nor do the 2 codes sound cat related so I doubt it.

If the MAF cleaning doesn't work you might look closely at the fuel pressure regulator. That can set code 0300. Usually though you get some rough idling with warm or cold restart problems not under load after warmed up issues. Still though it might be worth checking out. I think the check is to remove the vacuum line and if you get any gas then the diaphram has a leak in it and you need a new regulator. I think this link has all the info http://isuzufaq.ibctech.ca/ If not post back someone will have the scoop.

"I've never seen a cat affect fuel trim. You will get a OBDII code from one of the O2 sensors downstream of a cat." Now maybe you can clarify this quote of yours. He did have O2 sensor CELS. They could have been caused by bad O2 sensors, engine problems, or cat problems. No matter the cause, the computer will cycle fuel settings to try and get the oxygen readings within spec. Thus, a bad cat can lead to fuel trim (rich/lean) adjustments. At least that is my take. I welcome your feedback.

Correct. He had O2 sensor codes, but they were from the oxygen sensors upstream of the cats. These two upstream sensors do take a large part in determining fuel trim. The only function of the downstream of the cat(s) oxygen sensors is to monitor cat performance. They are not used in fuel trim calculation. No codes from the downstream O2 sensors means the cats are doing thier thing.

G/luck
Joel

First off let me thank EVERYONE who is trying to help, it is so much appreciated you can't know. For around $60 I have gotten it driveable, since it's only 10 min. to work. At the dealer I know I would probably be looking at $500-700.
Cleaned the MAF with alcohol and q-tips, being VERY careful. There was alot of black deposits around the front, behind the screen (I hope it wasn't a factory coating! It's gone now.) It did help some but not completely. The idle in Drive is somewhat better and the engine kicks down in "passing gear" easier. During the test drive I noticed it ran better when I floored it for a block then it ran NORMAL for a couple of blocks, then started "puttputtputting" again under part throttle, then full throttle for a block (it's raining so no ones out) and it ran good again for a couple more blocks. Any ideas?

Thanks again,

First off let me thank EVERYONE who is trying to help, it is so much appreciated you can't know. For around $60 I have gotten it driveable, since it's only 10 min. to work. At the dealer I know I would probably be looking at $500-700.
Cleaned the MAF with alcohol and q-tips, being VERY careful. There was alot of black deposits around the front, behind the screen (I hope it wasn't a factory coating! It's gone now.) It did help some but not completely. The idle in Drive is somewhat better and the engine kicks down in "passing gear" easier. During the test drive I noticed it ran better when I floored it for a block then it ran NORMAL for a couple of blocks, then started "puttputtputting" again under part throttle, then full throttle for a block (it's raining so no ones out) and it ran good for a couple more blocks. Any ideas?

Thanks again,
Brett

Change the plugs yet?

Might be worth, taking it to a place to have the Injectors cleaned (they hook up a bottle of pressurized cleaner to the fuel rail.

When I have a slight fluxuation in RPM's it was due to a leaky IMG (I know you said you changed yours).

-Ryan

You know, with all that's going on, I fergot to change the plugs, I looked at them but haven't changed them. I get paid Thursday so I'll order them then. I'm also thinking I may have done something wrong installing the gaskets (over torque, under torque, not clean the heads enough, etc...), everyone seems to think that should have taken care of the problem so I'm thinking of doing it again. Would it be a good idea to get two more, or can I just take out and inspect the ones I already installed?

Thanks,
Brett

I would order two more. If you pull the old ones and you don't have new ones to replace them then you're going to have to wait a bit.

If your find out they are ok, then you could just keep the new set as a spair or ebay them.

If you have the ion sensing system in your Trooper make sure you only use the plugs specified in the owners manual or you will likely set some CELs.

This series of posts has some IMG info including the torque specs. Can't vouch for the torque numbers as I don't have a manual handy.

Good luck.

http://www.4x4wire.com/forums/showflat.php?Cat=&Number=630907&page=&view=&sb=5&o=&fpart=1&vc=1 Is the link I left out of the previous post. The POS software here won't let me edit any of my posts.

# IB04-03-S001 FEB 04 Emissions - Misfire DTC's/Catalytic Converter Damage

I don't know of anyone with access to TSB but if you do here is an interesting one:

http://www.automotiveforums.com/vbulletin/showthread.php?p=2854894

info on the TSB above.

Well, finally got the plugs, I ordered them from sparkplugs.com because I could not find them in town except at the dealer. Changed them out but no change (they are excatly what came out, Denso) . So, I've:
1) Replaced the intake manifold gaskets
2) Cleaned the EGR valve and tube/port
3) Cleaned and checked PCV Valve
4) Cleaned the MAF sensor
5) Changed spark plugs
6) Tapped (BEAT) on the fuel rail
7) Changed fuel filter
It still misses and stutters at cruise and under acceleration, I've run out of ideas, if anyone has any suggestions please let me know, otherwise we'll have to take it into the shop on Monday.

Thanks for all your help,
Brett

Well, finally got the plugs, I ordered them from sparkplugs.com because I could not find them in town except at the dealer. Changed them out but no change (they are exactly what came out, Denso), still misses and stutters under acceleration and at cruise when warm . So... I've:
1) Replaced the intake manifold gaskets
2) Cleaned the EGR valve and tube/port
3) Cleaned and checked PCV Valve
4) Cleaned the MAF sensor
5) Changed spark plugs
6) Tapped (BEAT) on the fuel rail
7) Changed fuel filter
I've run out of ideas, if anyone has any suggestions please let me know, otherwise we'll have to take it into the shop on Monday.

Thanks for all your help,
Brett

Took it in ,it seems they think it is a coil going bad. Does anyone know a way to check for this, or just get one and replace them one at a time until the bad one is found? They're going to replace it and then call me tomorrow, wish me luck!

Brett

they can just move the coil to another spot and it should toss a code that the coil is bad in the new spot.

FYI: St. Charles sells the coil with boot for 103 bucks shipped.

Maybe you have water in your gas? Have you tried addind a bottle of HEET to your gas (cost 0.89); worth a shot.

Yep, that was it, it runs like a top now (WHEW!). I know the intake manifold was bad and the plugs had 50,000 miles so I really didn't waste any money or time, thanks to you guys. They say that the coil on cylider #2 was bad and the one on #3 is "breaking down". My question now is how are the cyliders numbered? That way I'll know which one it is.

Thanks,
Brett

Was the coil totally out? When one of ours failed it ran really bad, the miss was pretty strong. My wife came home one day & said the truck was running terrible. I drove it & felt that a plug had fouled, (we were over 100k on originals) so to isolate which one I unplugged the coils one at a time(turning off engine in between) until the engine didn't change or didn't miss even more. Then I swapped the suspect coil with the one next to it and the bad miss switched cylinders. What did they charge you for the coil? Amigo or rodeo02 if you are out therewhat is the resistance of the primary & secondary coils?

Rear
5 6
3 4
1 2
Front Is the order.

Don't know the coil resistance readings but unless they all fail at the same time you should be able to measure them all to find the suspect one(s).

good point!

Hey man if you put premium and it did run better that tells me that you have carbon deposits in the cylander. take the mass air flow if equipted off and the air filter where you have a strait shot into the intake and get a spray bottle of water and take the throtale up and down while spraying water into your intake witch if you have ever seen a car with a bad head gasket where it leaked water into the cylander it is clean as can be. Trust me with this just be carefull

Added this to the FAQ's
Rear
5 6
3 4
1 2
Front Is the order.

Thanks everybody for all your help, my Trooper is now happy and healthy! When the other coil goes I have the info to change it myself, and a place to get it from, plus I'm not scared to try to fix things myself (my wife's still scared though). When things go wrong again I know where to turn now.
Thanks again everyone, esp. Amigo-2K, Rodeo02, and Travelman!!!

Brett, aka "happy"trooperbrett

Trooperbrett - I agree with a previous suggestion that you put a new coil pack or two in there ASAP and keep the current problematic one(s) as a spare. If you don't you could be in for a bad suprise if one completely fails. With my luck it would fail in the wrong part of town at the wrong time of night and in bad weather.

More likely though the spark will just keep getting weaker and weaker. At today's gasoline prices even a teeny-tiny mileage hit from such a weaker ignition could cost you more than just buying a brand new one(s) now. I bought a used one off Ebay just for a trail spare. I have even seen supposedly new ones there for bargain prices. I have never priced a salvage yard but they might also have some less pricey options for you.

My Suv has been running very high idle, there is a red check mark flashing on the left side of the dash board on the torgue gear draft . everytime I move the gear to a different drive it jumps and make a lot of noise . i dont know what is wrong with it it burns too much gas, and it does not drive fast at all and lately it has been cuting off sometimes.
where it does not work. I just changed the starter recently. I dont its a starter issue somone said that the calibretor needs to be change I dont know wht that is. but the cars has more than one problem please help......................................