My age old problem...SOLVED Please Read!

[Synned]

I have had this problem since I got my car.
My problem is that when its warm out it happens almost all the time.
The car will hesitate and lose a bunch of power when it gets to this point. It will happen on cool days after driving a little, and on warm days it happens after like 10 minutes. After it happens the car is pretty much a dog.
It will stall much much easier, say if I am going from park to reverse and turn my wheel it will stall, even sometimes when i just go to reverse it will stall.
It's horrible. I'm thinking that the computer is pulling timing for some reason.
It runs smoothly...just NO power down low.
It has a basic tune up...plugs wires cap rotor, and o2's are new.
The ect is new as well. The MAF is a used one that I picked up because of previous problems with my own.
Now I'm pretty sure its a sensor thats causing this, I don't know what else it could be.
Maybe its the ACT?
BTW: This is an sn95.

 

[xpeteyjtx]

First thing I would do is pull codes

 

[Synned]

First thing I would do is pull codes

Nothing...no codes.

 

[Synned]

Does anyone think it could be injectors?

 

[HISSIN50]

Joe, ACT is not first on my list, though it is an important sensor (more-so on the 5N95 than a fox, IMHO).

Can you equate it running well vs running like a dog to a given engine temp? I know on mine that with anything over 195*F, it starts to feel limp. I dont know if it's a tune thing, a sensor thing or just an issue with my car (I dont think it's the last two really, especially since so many 5N95 guys are having the same issue).

On your stalling thing, if cleaning the IAC didnt help, you can bump the idle setting up (I'd use the idle stop screw and not the IAC bleed jet).

Good luck.

 

[Synned]

Joe, ACT is not first on my list, though it is an important sensor (more-so on the 5N95 than a fox, IMHO).

Can you equate it running well vs running like a dog to a given engine temp? I know on mine that with anything over 195*F, it starts to feel limp. I dont know if it's a tune thing, a sensor thing or just an issue with my car (I dont think it's the last two really, especially since so many 5N95 guys are having the same issue).

On your stalling thing, if cleaning the IAC didnt help, you can bump the idle setting up (I'd use the idle stop screw and not the IAC bleed jet).

Good luck.

Yeah, I don't have an accurate temp gauge (stock), but the temp gauge is always below the middle of NORMAL never above straight sticking up. I guess straight up is around 190*? The problem really seems to happen a LOT quicker with hotter ambient temperatures...say when its 90* and humid outside I won't be able to drive it normally at all- straight into 'limp mode'.
On cooler days like 70* it will take a little bit before starting limp mode, and it starts out ok and progressively gets worse.
The sluggishness is most noticable down low...high rpms dont feel affected as much but that could just be my sotp meter being wrong.

 

[HISSIN50]

I dont think your SOTP meter is wrong because what you're saying is congruent with what I feel as well.

I'm gonna fart around with my IAT (doing one of the no-no things that people always groan about) and see what happens.

 

[Synned]

Okay, let's see what happens.
I think I might pick one up from pep boys, try it and return it if it doesn't work.
It's only 20 bucks.
Someone mentioned fuel injectors give this problem I'm experiencing. No way I am shelling on 200 on a guess though. But I guess if the fuel injectors were cruddy I would be running either rich or lean but it doesn't seem like it and the plugs don't look that way. It feels like timing, but its so hard to read my balancer sometimes but I'm going to take a look while its running like a dog.

 

[Synned]

You guys are going to kill me...but...
I am going to buy one of those IAT resistors on ebay...the ones that trick the ECU that the incoming air is cool and dense.
Its only like a buck so I'm going to give it a shot.

 

[Synned]

Well I checked the timing while the car was being a dog.
Left the spout in...and it was high 20's at idle. I revved it and saw it jumping into the 30's.
I guess the computer isn't pulling timing, so that leaves fuel and spark?

 

[HISSIN50]

Well I checked the timing while the car was being a dog.
Left the spout in...and it was high 20's at idle. I revved it and saw it jumping into the 30's.
I guess the computer isn't pulling timing, so that leaves fuel and spark?

Joe, this is a little strange perhaps. What's your base timing at?

I run 6* base right now (109*F today - I have the typical 94-95 GT ping-thing to deal with). Installing the SPOUT brings me to 21*. If I rev it to 1500 RPM I see 35-40* total timing. I originally puked when seeing this but in researching it a bit (Wesley's articles, etc) it seemed to not be completely out of line (part of the T4/U4 tune having too much timing down low and not enough fuel).
I guess I'm saying that while there is room for a lot of subjectivity, I'd have expected to see your total timing be higher when you revved it up some (I'm guessing your base timing is 10-12* SPOUT out, given your SPOUT in timing).

I figured I'd toss that out just for comparison's sake.

Good luck Joe.

 

[Synned]

Joe, this is a little strange perhaps. What's your base timing at?

I run 6* base right now (109*F today - I have the typical 94-95 GT ping-thing to deal with). Installing the SPOUT brings me to 21*. If I rev it to 1500 RPM I see 35-40* total timing. I originally puked when seeing this but in researching it a bit (Wesley's articles, etc) it seemed to not be completely out of line (part of the T4/U4 tune having too much timing down low and not enough fuel).
I guess I'm saying that while there is room for a lot of subjectivity, I'd have expected to see your total timing be higher when you revved it up some (I'm guessing your base timing is 10-12* SPOUT out, given your SPOUT in timing).

I figured I'd toss that out just for comparison's sake.

Good luck Joe.

I'll check that again tomorrow- Maybe it is timing. The car is running ok now so I'll wait untill tomorrow after I've driven for a bit.
It's a little hard to tell where the timing pointer points on the balancer, but ill ask someone to hold it at 1500rpms while i look.
Yeah, my base timing is around 12*.

 

[feifong]

Its da fuel pump Have fun

 

[HISSIN50]

Its da fuel pump Have fun

In what he has said, how did we reach this conclusion? I certainly could not have, given the info provided.

 

[Synned]

Its da fuel pump Have fun

I have had 3 people told me what my problem is, the distributer, injectors, and now fuel pump. I don't think it's all three so do you have evidence or even a reason why you think its the fuel pump?

The only other thing I can think of that relates maybe to a fuel pump is that the car always take a long crank to fire in the morning (maybe because low FP).

 

[whtpny]

Well here is another one to ponder. How is your compression? Blowby? Leakdown test? I have seen quite a few cars with some miles get warmed up and loose all sorts of power due to being just plain wore out. When things start to expand from heat they will not always seal as well. Hard cold cranks can also be from lack of the engine retaining as much compression as it used to untill it cranks and builds it back up a bit.

 

[HISSIN50]

The only other thing I can think of that relates maybe to a fuel pump is that the car always take a long crank to fire in the morning (maybe because low FP).

Joe, for some reason the pressure bleeding off via the pump check valve is really common on 94-95's (I havent nailed down why). If you have a FP gauge, install it and watch pressure while the pump primes in the morning. If it takes two or three primes to get over 30 PSI, that's that. It doesnt necessarily mean anything bad (the FP check valve, FPR, fuel filter, pump itself [unless other fuel volume issues are present] or injectors leaking are likely candidates, in that order IMHO). If this is the case and you want to chase the issue, fuel line crimpers can be used to test the system (we can post more on that if needed).

Good luck bud.

 

[Synned]

The starting issue is not as much a problem to me as this hesitation-slowness.

Today I bought 3.3k resistors from autozone, and used it instead of the IAT.
No difference. Didnt think it would, but for $1 who cares.

I don't know what else. I also checked the timing today, the timing really looks like its fine.

I guess that leaves fuel, an ignition problem, or compression? I doubt its compression, the motor is barely over 60k and has been babied for 50k of those miles.

Its weird because once my revs get over like 3k it pulls like it should, but under that is horrible. If i floor it its like wow, horrible, like a 4 cylinder car. It starts to pull as you get higher r's.

 

[HISSIN50]

Joe, Once we broke 110*F here, and my motor temps went over 200*F, I was in the same boat as you - it felt like there was something stuck under the gas pedal.

I havent had time to figure out what's up with it yet (I wanna see PID's while this is occurring).

No help from me, but you're not alone. Thanks for sharing the resistor info. Nice to know that's not a fix...............

 

[mercurycapri]

Same problem as my car. Hope its not a bad motor.