Ok my car has been running great, but recently between 2000 rpm and 3000 rpm it was stuttering a little. I figured that my plugs were fouled, so I replaced them. While driving home everything was going ok until I got into the boost a little. Boosted fine but after it started stuttering again. I wanted to see if pushing the engine was making it start stuttering so I did a WOT run. After that it had no throttle response below 3000 rpm and sounded like a lawnmower. My vacuum was down to 10 inHg. But as soon as it passed like 2900 rpm it started acting fine. Then when it was idling it would get really rough low vacuum and idle and then recover. I let it sit for a while and it got better. Then I pushed it once more and the symptoms returned. I don't know what this is. My engine has 20k miles on it and has never overheated or detonated. My turbos have about 4k miles on a rebuild, and here's one thing that I thought might be the problem. The primary compressor wheel when I got it seemed a little tight. Could my turbo be sticking and causing this or am I lucky enough to have a stupid problem?

 

Did you have any boost before 3000rpm and if not did it suddenly increase faster than normal? I had a problem where it would run terribly before 3000rpm then the power would come on very quickly. The problem was a cracked check valve. At about 3000 rpm the turbo system starts prespooling the secondary turbo. I worked through the turbo system based on this site, http://home.istar.ca/~dvandit/turbocharger.htm
Sorry I could not find which check valve I replaced in my notes. Hope you can find whats going on. BTW my problem started shortly after rebuilding my turbos, I must have cracked the check valve while working on the system.

 

If my primary compressor was sticking would that cause low vacuum? I was thinking that that was my problem, but I don't see howit could cause lowvacuum. I'm going to wire my precontrol door open and see if it gets better. If it doesn't then I know it's not the turbo sticking. What else could it be?

 

I wired the precontrol door open letting the exhaust go to both turbos and it still acted stupid. The problem seems intermitten because it will idle fine and then after a few minutes bog down and shake like hell. Whenever it bogs the exhaust gets really quite sounds almost like it's missing, but I've never heard a rotary miss, so I don't know for sure. Does anyone out there have a clue about this?

 

Has anyone else had a problem like this before?

 

I am sorry, I really cann't help you in your situation but I wanted to tell you that your avator rules

 

Thanks it Ren from Ren and Stimpy

 

Make sure the hose going to the boost sensor is connected.

It is on the firewall on the driver's side. There is a little hose that connects to the bottom of it, and the car really acts strange when this comes off.

Patrick

 

The MAP sensor is hooked up fine. The thing is, though, that my ecu is sending up a code 13=MAP sensor. But my MAP sensor came loose a while back and I never reset it so I'll have to check that out. Could it be a bad coil? How do you check for that?

 

I tested my coils and they were all good, but then I tested my wires and one of them had like 14k ohms(L1) where the rest of them had 3k ohms. Hopefully my problem was just a bad wire snd I'll be up and running here shortly.

 

Put new plugs in and it runs like a charm. Why do I always suspect the worst.