Car Is HESITATING; I have Tried Alot of Things and I Need Help

[98autogstspyder]

Hello Fellow DSMers. I am having some issues with my '92 Eagle Talon right now. The car started hesitating real bad (almost feels like pulled timing) about a week before I took the head off the car. I did a compression test , discovered I had a few valves that were slightly bent, so I fixed that problem. Compression is up to par. I started the car up and took it out for a drive. Right as the car is about to hit boost, the car jerks and feels like it is being "held back". I have described the symptoms as best I can. I do not have a boost gauge yet on the car. Turbo has no shaft play and I can hear the turbo spooling loudly.

'92 Talon TSI AWD 5 Speed:
The car's only mods are: ported 2g exhaust manifold, balance shaft elimination kit, 2.5'' catless exhaust from flex section back, ngk plugs and wires, crushed 1g bov, arp head studs.

I have replaced: knock sensor, o2 sensor, fuel filter, plugs and wires are new.
Car is set to 5 degrees advanced like it is supposed to be. All timing marks line up.

The hesitation problem was a lot worse. It got better after replacing the stock exhaust system to the 2.5'' one I have on the car now. Then I did a boost leak test and found a large leak where the j-pipe meets the turbo. Fixed that and the car's response got better. The hesitation problem now occurs when I go WOT only. There is another leak at the throttle body seals I have not yet fixed yet. It did not sound that big, so that is why I think my problem lies else where.

I suspect that it may be the ecu. The cover for the ecu does not match the ecu itself. It was "repaired" back in 1999 according to a sticker on the box. The ecu is covered with sillicon. I have no "Check Engine Lights." I tried logging my car, but for some reason the logger would not work. My diagnostic port might be bad or the cable to the logger could be bad.

If any of you have experience with a Hesitation Problem please share it with me.

 

[oldman]

1. If the logger doesn't work, how did you tune the safc?

2. Plug type/gap?

3. Compression numbers?

4. How much pressure and for how long was the intake able to hold during your last leak test?

5. Clean the air filter.

 

[ftltalon]

1. If the logger doesn't work, how did you tune the safc?

read that again, no mention of a afc.
try using annother ecu if you thinks yours is fubared
i think is annother boost leak if it only does it when your building boost

 

[98autogstspyder]

I thought I made this clear but I will re-clarify. This problem is for my '92 Talon AWD. The car in my profile is a 2g, a '98 gst spyder. My 1g does not have an afc installed in the car.

Cleaning the airfilter.... hmm didnt think about that.

The compression numbers are as follows:
1 - 150
2 - 160
3 - 145
4 - 160 (cylinders 3 and 4 were still cold when we did the test so they should read a little higher)

The spark plugs are stock ngk bpr6es. They are about 4,000 miles old but should be replaced. I have new ones at the house, I will regap them accordingly. The car is not missing it all, there is no misfire at all. That is why I am steering away from an ignition problem.

Thanks oldman, I hope this helps. I love that name by the way hehe I feel funny calling you oldman.

 

[oldman]

I thought I made this clear but I will re-clarify. This problem is for my '92 Talon AWD. The car in my profile is a 2g, a '98 gst spyder. My 1g does not have an afc installed in the car.

Sorry about that, I have a tendency to think faster than I read sometimes.

Cleaning the airfilter.... hmm didnt think about that.

I'm assuming you have k&n type, if you have not clean them in a while definitely try that.

The spark plugs are stock ngk bpr6es. They are about 4,000 miles old but should be replaced. I have new ones at the house, I will regap them accordingly. The car is not missing it all, there is no misfire at all. That is why I am steering away from an ignition problem.

Hard to say, at least check the gaps on the old ones. Besides that, I would fix that leak at the TB then pressure test again until system is able to hold 20psi.

Thanks oldman, I hope this helps. I love that name by the way hehe I feel funny calling you oldman.

You're welcome, the name gives people a false sense that I actually know my sh*t.

 

[98autogstspyder]

I'll check the gap too when I get a chance.

But as far as the ECU being the culprit, how possible do you all think that is? It has not thrown any codes and I dont smell anything fishy. I know I still have that boost leak there and I will fix it asap, but I just want some ideas on what other possibilities there may be.

 

[oldman]

I'll check the gap too when I get a chance.

But as far as the ECU being the culprit, how possible do you all think that is? It has not thrown any codes and I dont smell anything fishy. I know I still have that boost leak there and I will fix it asap, but I just want some ideas on what other possibilities there may be.

I personally do not think it's the ecu or it should effect more than just during WOT, however it wouldn't hurt to double check with a known good one. How much psi is WOT anyway?

 

[98autogstspyder]

the car is at stock boost, with the boost control solenoid eliminated. all I have is the stock boost gauges which only reads about 9 or so. i will get an accurate one as soon as i have some money to spare. yea if the ecu were bad it would probably be affecting more than one thing, but you never know. i need to eliminate my boost leak first and see if that does it. thanks for the feedback.

 

[Spoolin4Ever]

Have you INSPECTED the ECU? Sounded like you are saying no fishy smell in the interior, but that you have not pulled it out, opened it and sniffed real close.

Oh I just read, it's covered in silicone? You mean you can't open it? Wow interesting.

How many miles on the turbo??

TPS maybe?

Tried any SeaFoam lately?

 

[98autogstspyder]

Well I figured it out. The CAS was upside down. It was 180 degrees off. I discovered this by trying to set the timing to realize that the marks weren't even showing up.

Thank you to everyone who helped out.