I need some true dsm experts to help me out once and for all....

[my95tsi]

Ok nobody has yet helped me out with this problem and it has given me nothing but hell. I'm considering selling my Talon because this has gotten so bad. Here's the deal my 95 tsi will not idle on a warm startup. If i start it up in the morning it'll run just fine. If i shut it down quickly and start her back up it's fine. But when the car has been driven for atleast 20 minutes or more and i shut it down and start it back up about 30-90 minutes later the car idles at about 200-450 rpm's and shakes violently wanting to die. About 50% of the time it wil die and it takes up to the 3rd startup for it to finally run. When i rev it up while it's idling low it revs just fine but it doesn't sound or feel normal. The car still shakes and it sounds like it misfiring just at a higher rpm. It sounds like popcorn popping when i rev it. But it takes about a minute for it to finally get back to normal. The car will drive just fine and when i come to a stop the car will idle normal. My isc is fine so i ruled that out because when i disconnectted it the car will still idle bad while warm. My girlfriend has told me that my car smells like gas when we get out. But i also have a test pipe and my car has always smelled bad. However i seem to notice a slight smell. I really don't know the deal and it's starting to get very annoying. I have to deal with this everyday, i hate to ever start her back up. This morning i started my car and something ver different happened. The car didn't idle high it just idled like it is when it's warm and when i dove around and came to a stop the cars rpm would dip to like 200 and bounce back to normal. I've had this warm idle problem for about 3months but my car has never done this before, it was the first time. I really need some proper diagnosis because it would be greatly appreciated.

 

[talon monster]

just a statement of experience not a professional mech.. there maybe many differences between our cars. mine a 1990 talon tsi. mine started with the feeling of less power, only some times. then the idea of needing a cat. but got worse quick. the smell of gas was always present when i came to a stop after the car acted up. then the car seemed to run better cold in the morning. then accelerating the car seemed to bog. then while bogging down the popping started. then it felt it felt like the car was always being forst to run. also while going on the gas milage sucked, bad. but at night when cool. if you could get it running fast it drove fine and fast. with no popping. a passing friend said my tail pipe was glowing red. had to go on a 25 mile trip. forcing the speed limit the car drove bad. and used half my gas. so going back i tested the top end (only to get me as close as possible to home before the gas ran out). the car drove fine and it used little gas. found one mec. who found the problem. the car was reading colder than it was. so the car was dumping stupid amounts of gas. not the sensor but the computer. i changed the computer and the engine ran fine till know. the mec. only charged me 50. it also helped he had a computer out of his to test my car before i bought parts..

again just a comparison after reading yours. because if i was my car wouldn't have its own post.

 

[GTM]

Ok nobody has yet helped me out with this problem and it has given me nothing but hell.
...

Have you checked the coolant level in the engine (not the overflow), does the heat come and go seemingly at random or when accelerating?

I'm thinking temp sensor (not temp sender for the gauge).

Let us know.

Cheers,
GTM

 

[my95tsi]

talon monster, I'd say that my problem is not as bad as yours. I really don't notice a decrease in gas mileage or bogging while driving. My issue is strictly a warm idle problem but the car seems fine and pulls like normal.

GTM, what do you mean by checking the coolant level. The coolant level is normal. Also what do you mean by the heat coming and going at random? Would i have to check this by using my pocketlogger?

 

[GTM]

...
GTM, what do you mean by checking the coolant level. The coolant level is normal. Also what do you mean by the heat coming and going at random? Would i have to check this by using my pocketlogger?

As long as it _is_ full then unless the sensor is starting to malfunction at running temps it won't be a factor. Have you checked the cam and ign timing? Plugs and wires could do this also.

The popping could be a lean condition or too much advance on intake cam. Oh, almost forgot fuel filter plugged, fuel pump or pump relay starting to fail when it gets warm.

You are just going to have to eliminate what it's _not_ until you find what it is. Keep us updated with progress or questions as you conduct tests.

Cheers,
GTM

 

[my95tsi]

Yeah i have checked the plugs which a bpr7es and they are a greyish white color (more white) but they checked out to be perfectly fine. The wires are just over a year old and seem fine. My question is how can my timing be off when it was previously fine for the past 2 years since i've done my t-belt and just start going out now? Also what would timing have to do with a warm idling issue and not all the time even when coming to a stop?

I myself have considered fuel filter and fuel pump but have not yet checked them. I don't know how to check my fuel pump becuase it's stock and i can't hear it runing even when it is. What about a bad coil could that be a problem? My only concern is why does it do this only when it warm and only for a minute or atleast until i start her up again? The warm thing has stumped me beyond belief.

 

[GTM]

...
My question is how can my timing be off when it was previously fine for the past 2 years since i've done my t-belt and just start going out now? Also what would timing have to do with a warm idling issue and not all the time even when coming to a stop?
...
I don't know how to check my fuel pump becuase it's stock and i can't hear it runing even when it is. What about a bad coil could that be a problem? My only concern is why does it do this only when it warm and only for a minute or atleast until i start her up again? The warm thing has stumped me beyond belief.

Not meaning to be flip but why should you get a flat tire... it's your turn or (s**t happens). What does the book say is belt life, 40,000(?) miles, 2 years(?). At _least_ twice a week on DSMtuners some belt has skipped or broken for a variety of reasons.

When the engine is cold it adds more fuel and retards the spark as it gets warm these change. These are not absolutes, we are trying to narrow down the possibilities which can influence the problem as you have described... they don't have to be right for your condition. however, they are educated guesses from decades of past experience. They went to belts over chains because it was cheaper to make not because they were superior, but along with that came increased maint for them which they traded off with spark plug life etc.

Putting a fuel pressure gage in the system would tell you how the pump is behaving, this can be influenced by pressure regulator and relay. There are static tests which can be conducted but you will need a manual to establish procedure or you may find info on Vfaq.com.

Coils as in relays and spark generating fail more often when hot, wires break or short out, they then cool off and reestablish connection and act like nothing has happened. Temp sensor resistance changes over time or can fail like a light bulb. I can go on and on with this but until you are able/prepared to get involved, add some more info I'm spinning my wheels with the whys and what iffs. I'm just as analytical as the next person if not more so but you have to establish some logic and a course of action. If you don't have a _good_ trouble shooting manual this is going to be impossible with what we know.

Cheers,
GTM

 

[my95tsi]

DTM- I really appreciate ythe knowledge and logic that you have demonstarted to me. I just like things esplained to em when they don't make sense andnow they do make sense. I do have a pocketlogger and i'm not new to cars but i'm not very good at diagnosing problems because i relaize that it really couild be anything. The only thing that i have to mention is that even when the car is warm it idles fine unless i have restart it. I'm going to perform the fuel pump test but i think a pressure gauge would work better. The fuel pump obviously works or i wouldn't be driving the car but itmay have issues when being restarted. I do have a datalogger so i'm going to check coolant temps while it's acting up and i'll also cvheck timing. My best bet would be to just start recording many different functions as my car is acting up, up until the point where it starts running normal again. According to my a/f gauge my car does get very lean at idle when its acting up it will sit at .06-.08.

 

[GTM]

...
I just like things esplained to em when they don't make sense andnow they do make sense. I do have a pocketlogger and i'm not new to cars but i'm not very good at diagnosing problems because i relaize that it really couild be anything.
...
I do have a datalogger so i'm going to check coolant temps while it's acting up and i'll also cvheck timing. My best bet would be to just start recording many different functions as my car is acting up, up until the point where it starts running normal again. According to my a/f gauge my car does get very lean at idle when its acting up it will sit at .06-.08.

You are welcome. Funny business a few of those who are not having a problem find fault with my explinations and trash me for writing long posts but not those who are having the problem. It's obvious you wanted to know and what matters it's you with the problem and not those who wish to be ignorant. You don't learn anything when you don't ask questions.

The pocket logger may or may not reveal the source if it doesn't sample the item that's failing so don't be too dependent on it. Sometime you can get too bogged down with getting results from some device that you loose the focus. When you have seen thousands of similar complaints you get so you can narrow it down to just a few things in a hands on process. But sitting behind a monitor presents a real challenge when all you have are words which may not translate from one language to another. One of my favorites is the difference between a doctor and a mechanic is their patients talk to them... I talk to my cars a lot but never get an answer. Keep us posted

Cheers,
GTM

 

[my95tsi]

Should i consider bad coil pack to be an issue and how would i go about checking this?

 

[gstowner]

Im having the same problem. I think its fuel related. My guess is the fuel pump.

 

[Defiant]

Yeah i have checked the plugs which a bpr7es

Go back to 6s, like the motor wants.

 

[my95tsi]

The 7's are fine they have been fine for the past 2 years. I'm not trying to be an ass but AMS recommended them to me since i have turned up the boost. Plus they are not the cause of my idle problem.

Go back to 6s, like the motor wants.

 

[oldman]

http://www.taboospeedshop.com/diagnostics.htm

Look under "defective idling continuation", it should help you narrow things down a little. I would also check for vacuum leak as well, especially around the TB area. Good luck.

 

[gstowner]

I wonder if it could be the ac switch. That would explain why it does it when its hot. Cuz you probably have the ac on. Its only done it to me twice and I think both times I had the ac on. (even though it doesn't work I think there is either a leak or a bad compressor)

 

[my95tsi]

No i don't have it on.... AC wouldn't cause a misfire if i reved it up

 

[AMS Eric #2]

No i don't have it on.... AC wouldn't cause a misfire if i reved it up

Do you still have your vacuum lines going thru the fuel pressure regulator solinoid on the firewall? This is one side effect of eliminating the solinoid and running the line straight from the manifold. Under a hot start, the solinoid closes the vacuum source to the FPR, making your fuel pressure higher, which helps to eliminate the lean condition caused by heat soaked fuel in the lines and rail.

I have my FPR solinoid eliminated and when hot starting, I have to give my car a few good revs to get it to idle correctly. I guess I'm just so used to doing it, I hardly even think about it anymore.

You should check the operation of the FPR solinoid if you do still have it intact. Pull the vacuum line off the FPR, and put your thumb over it while having a friend start the car when hot, or during a time you usually experience this problem. For the first 15-30 seconds or so, you should feel no vacuum at the line that connects to the FPR. After a set amount of time, the solinoid should open giving you vacuum.

 

[CYCLONE]

I would try new plugs. Cheap and easy start to eliminate stuff. Its always the stupid
and easy things that we overlook that endup being the problem.

My car would have a similar idling and poping issue just before reaching normal
opperating temps. Plugs took care of it.

 

[my95tsi]

AMS Eric #2- I haven't touched the fpr, as far as i know it's stock. I'm still on the t25 and my fuel system is stock. My car started to do this over 6 months ago but it would only happen about once a month or more. I thought it was turbo related because i didn't cool my car down enough. Now it does it all the time. However it hasn't done it in the past day but then again i haven't driven my car to where it's really warm, only short distances.

 

[Defiant]

The 7's are fine they have been fine for the past 2 years.

Ah. But, is it now? And are there 7s in there now instead of 6s?

I'm not trying to be an ass but AMS recommended them to me since i have turned up the boost. Plus they are not the cause of my idle problem.

It's an awfully cheap, quick, and easy thing to try, but suit yourself.

 

[my95tsi]

If you guys think i should try it i'll throw some 6's in there. I persoanlly think it's a waste of money but who knows. I'm also going to do a leak down test this weekend.

 

[heavyD]

If you guys think i should try it i'll throw some 6's in there. I persoanlly think it's a waste of money but who knows. I'm also going to do a leak down test this weekend.

It's not like BPR6ES plugs are expensive. I just read this thread and as soon as I saw that you were running colder plugs on a stock setup a light went on in my head. With a stock fuel pump and a T25, you aren't running 17 - 19 psi so why would you need colder plugs?

 

[my95tsi]

7's just don't hurt anything though. I checked out the plugs and they look fine. If i throw in some 6's and they fix my warm idle problem then it's fixed but i'm 95% sure it won't be....

 

[GTM]

If you guys think i should try it i'll throw some 6's in there. I persoanlly think it's a waste of money but who knows. I'm also going to do a leak down test this weekend.

Keep the 7's as summer spares and long trips. Did you ever check the the temp sensor or get any info from your data logger?

Cheers,
GTM

 

[my95tsi]

Keep the 7's as summer spares and long trips. Did you ever check the the temp sensor or get any info from your data logger?

Cheers,
GTM

Haha, long trips?? I do long trips about twice a month just to see my girlfriend. 4 hours one way. As far temp sensor go, no. The problem is my car hasn't done it in about 2 days but i know that if i'd run her had or drive for 20-30 minutes or so my car would start to act up when i restarted it. I drive my car a lot and i drive it long distnaces a lot. Like i said this has been an ongoing problem in the past 3 months but it doesn't seem to effect the reliability of the car. It's never hard to start and it only die's on a warmm start but then again only about half the time will it actually die. I will mostly stumble and stumble for about 30 seconds or more then finally resume a better idle after it works itself out. I'll keep you updated, i plan i running alot of test of her this weekend. Could this possibly be a bad injector dumping excess fuel into the motor when i shut it off? But then again that would probably make it hard to start.