So I ordered some boost jets and installed them today. I took it out for a drive after the install and it would cut out at 8psi. So I brought it home and took them out. Hooked it all back up and left to go to my sons doctor appointment. I pulled out and I heard a sound under the car like a rock or something hit the bottom of the car. It did this twice in a roll. Assuming this is detonation. Got on the interstate and it was acting fine then I gave it a little gas to pass a car and it hit 0 psi and cut out like it was hitting a governor. I heard the sound under the car again when this happened. It would not get over 0 psi the rest of the way until I came to a stop getting off of the interstate. Once I took back off it would boost fine. Haven't started home yet. Don't know if it's going to do it again. Probably will with my luck.

Anyone know what's going on here?

 

I wouldn't think that's detonation if it happened while pulling out of the driveway, but I could be wrong.

 

It was under load. I was in 2nd around 4k rpm's when it did it.

On the way back home I got on it a little getting on the interstate and it acted fine. Then tried to accelerate in 5th and it lost power instantly. Boost was at about 6 psi when it did it. It also made the noise again and this time it sounded like a hammer hitting something underneath. It was real apparent it was coming from the drivers side. It never kept me from going over 0 psi again though. It just detonates and loses power now.

 

Just checked for codes and it shows 55. From what I understand that means there is no codes.

 

Just took everything off that I took off this morning. Didn't find anything out of place. Put it back together. Took it back out on the road and it ran strong as ever. Started back to the house and at 60mph in 5th I punched it and boost got up to 6 psi then it cut out and made that tapping sound again. It almost makes me think that the waste gate is getting stuck and making the popping sound, but would that make it cut out?

 

Hmm I imagine if the wastegate's stuck open you couldn't build any boost. I wonder if it would make such a loud sound though. Not sure how accessible the thing is, maybe check that out if you can?

 

I'm just curious if it's only going to do it in 5th now. Couldn't get it to do it in any other gear earlier. The computer showing no codes doesn't help figuring it out.

Might try calling z1's tech line tomorrow and see if I can get any ideas from them.

 

Well called z1 and talked to John and he said it sounds like a turbo is trying to seize up. He recommended running some Marvle Mystery Oil and doing an oil change. I was going to change the oil today anyways so let's see how that does.

 

Well I'm 90% sure the drivers side turbo is stocking. Went to autozone and got some marvel mystery oil and noticed on my way there the sound of the drivers side turbo was cutting in and out.

Brought it home and changed the oil and put the mystery oil in and let it idle for about five minutes. Took it out and it was still sticking. Drove about 15 miles and it doesn't refuse to boost anymore. At half throttle I can hear the drivers side turbo cut in and out. At full throttle it opens up and boosts normally.

Going to let it sit over night now and see how it does tomorrow. Unfortunately I'm thinking about putting a for sale sign on it. It's just eating me out of money. I really love the car and don't want to get rid of it. If I had another vehicle to drive I would park it and save the money up for some new turbos.

I know even if the mystery oil works and does free the turbo up it will eventually go bad and still have to be replaced.

If I do decide to sell it I don't know how much to sell it for. Any ideas? '90 2+2, TT swap, z1 ecu upgrade, dual pop chargers, z1 urethane mounts, upgraded weld on exhaust, no a/c or p/s, hand sized dent in drivers door, and a bad turbo lol?

Funny thing is I just got called and told I got approved for a job making really really good money. Might get to keep it after all. Yay lol!

 

Hope that stuff works and you keep the car man! I don't get it though, you said "it doesn't refuse to boost anymore". Isn't that good? And at full throttle boosts normally, sounds good too, even if it may be on its way out. And congrats on your job btw!

 

At half throttle it still cuts in and out. That only means its going to go out in the near future.

Thanks on the job. Not only will I be able to fix it, but I will be able to pay someone to fix it. Won't be able to do it myself due to long hours.