Something weird at 3500-4000 rpm

[Bunta]

Ok so here it is, when i start to floor the pedal (happens on every gear) and the rpm goes up, the boost kicks in, and right when it hits 3500-4000 rpm the car all of a sudden bogs, chokes, lags, or almost dies (the feeling is like when it's your first time driving and you really haven't learned how to balance the first gear yet, so it chokes and nearly dies), so then i just shift to the next gear and it then it seems fine again. It's like the car can't go past 3500-4000 rpm.

It's weird, to me but hopefully not to you guys.

The car does have a pretty big leak coming from the turbo manifold gasket.

[At-Least-It's-An-Evo]

Chu, it's a boost leak Paul probably never fixed. ;)

[Kracka]

Plugs, wires, boost leak check.

[Bunta]

Well from what Paul was telling me it was the bad Throttle body or throttle cable (paul said you said Anthony had the same problem so he swtiched the throttle body and then it all seemed fine) which im not sure he's correct on, so right now i was wondering if i should go to my workplace and get the intake manifold/throttlebody cleaner and spray it down.

Im kinda thinking this "leak" is that HUGE leak from the turbo manifold.

oh yeah does anyone have the unlimited carfax history deal, i really don't want to pay $30 for one car.

vin# 4E3CT64U0ME074105 (not sure if the "0" are zeros or "o")

[Andrew7dg]

Ok I am just going to add on to this forum also because I am having the same problem however I have been told that it could be the fuel pump that is given me problems. I hope Bunta won't mind

Symptoms are when I start to rev up to 4000 rpm the car starts to bog down and hesitate. The boost guage (which is the stock one and I should get an aftermarket one) says that it is getting like 13psi of boost.

Would the fuel pump have the same symptoms as a boost leak or is this for sure a boost leak problem?

I do have a 90 car with origional ECU and heard that those start to break down after a while and the first thing it seem like is going to go is the fuel pump but it is really the ECU. Am I getting this right or did I hear a bad rumor?

The funny thing is that before I bought the car the person said they did a leak down test on the turbo system and couldn't find any leaks so they suspected a bad fuel pump.

Thanks for your help

[Andrew7dg]

never mind! i fix the problem
yay for me

[thom1301]

never mind! i fix the problem
yay for me

What fixed the problem?

[Andrew7dg]

What fixed the problem?
Well remember I just got this car a week ago and I am kind of working out all the bugs yet. The problem kind of, sometime, but not all of the time, went away now. I replaced the fuel filter and I think that fixed it, or it did something.
However I just ran into another problem where my car is sucking gas now. One problem goes to another i guess. At first I thought I have a leak where the fuel filter is but that doesn't seem to be the problem. I would really like a data logger to see what the heck is going on. :confused: I need help:(

[Andrew7dg]

Ok I just got done changing fluids and checking everything on the car.

I found out (well I got help from someone else down the steet) that the problems are my spark plugs. Now don't bash on me too much because I am new to the Turbo DSM world and NOW understand the importance of spark plugs and brands. I now know NGK spark plugs are junk. They were new when the previous owner bought them and they fouled up. They would hesitate at the upper rpms and sucking fuel at the lower rpms. So I put some Sea Foam in the tank to clean everything out and it is running much better. I chose the copper autolite spark plugs. Cheap and they are working quite well so far as I can tell!!

Now my car is running like it should!!!!:D

[JET]

I now know NGK spark plugs are junk.
Actually NGK's are the plug of choice! The problem is that they probably were not gapped right or they just needed to be changed. You should be gapping at .026 - .028", depending on boost.