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Discussion Starter #1
Hey guys I just recently bought a 1989 Targa top Supra with a freshly rebuilt 7mgte and a newer paint job, the car won't rev past 3000 Rpm. The guy before me had the engine rebuilt by Canadian engines and put it in with his dad. He could never get the revs above 3,000 rpm after he installed the engine. He had it towed to a few different shops that couldn't figure it out and told him to take it back to the people who built the engine, he couldn't afford it anymore he told me. What we have been doing is testing every sensor by the book and we have also re calibrated the TPS and made 100% sure that the cam position sensor is in the right spot. We have tested every sensor to be within specs and we still cannot get the car to rev past 3000 RPM the fuel filter has been changed fuel pressure is 45 PSI. I have 3 different used AFM sensors and I have no clue if any of them work there is no check engine lights(bulb works). If I press the gas hard and hold it the car bogs and pops out the intake, unplugging the air flow meter makes the car not start. If i slowly rev it we can get 2500-3000 RPM.

I'm kinda losing my mind on this one any idea's would be much appreciated also please let me know if you need more information as I am kinda tired so I may have missed a few things.
There are no codes present. It has a hard time starting cold 2-3 turn overs....idles okay. Slowly revving it is the only way to bring the rpm's up to 2000-3000, if I press the gas hard it will stay around 1500 and make hard popping noise and shake violently. The cam position sensor is in spec tested air gap and ohm's readings, we have tried several different timing spots from 0 to 15 degree's. No idea what's wrong I have opened the ECU and checked for fried components. Checked all grounds and sanded them. Every component is in spec from vsv to fuel resistor pack, injectors working, took exhaust off at the turbo to see if it's restricted... for some reason she just doesn't want to go outta limp mode.

I'm thinking it's the afm sensor.... I know another guy with a supra but he keeps blowing me off every time we set up a meeting. I don't want to send mine off to get rebuilt if it's not the problem it's about 400 bucks...and I've already bought a used one and it didn't do the trick.
 

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Any codes? And check your cam timing. Set the crank to 0* and the cam markers at 12 o'clock. It's kind of easy to get one or both cams a tooth off sometimes.
 

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Discussion Starter #3
I know the intake cam is right on the money but it's hard to access the exhaust side but i will give it a shot thanks for the advice. No codes present at all.
 

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What? If you take the cam cover off the cam gears then you'll see both. Don't try to line them up by the cam lobes. Use the marks on the gears.
 

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Were you able to check the fuel pressure with the engine running? If so did you check the pressure while you were trying to rev the engine at the same time? A fuel pump that won't keep up pressure won't throw any codes.

We had a similar problem years back and it turned out to be a FILTHY gas tank. Had the tank cleaned and replaced fuel pump and problem solved.
 

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He said it was at 45psi. If the exhaust cam is off, so is the CPS. Having the exhaust valve stay closed for another 4 or 5 degrees will cause issues like this, mainly the shaking and popping.
 

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Discussion Starter #9
tried another Lexus ls400 v8 black box today and no luck same symptoms that's 4 AFM's so far BTW got a steal on a lexus body and black box for 27 bucks at pick a part new arrival. Not using the lexus body until I get the proper injectors etc...
 

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Discussion Starter #10
I don't know what the fuel pressure is under load as a shop did the test and it was 45 PSI at idle I have clamped the return line and no difference so it's not the Pressure regulator. Could a bad EGR or a EGR vacuum leak cause these symptoms or even a boost leak ?
 

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It could if the EGR is stuck open. It's kind of rare that happens though. Here is the vacuum diagram (link).

Was the crank at 0 when you checked your cam timing?
 

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Discussion Starter #13
Yes it was set at 0 TDC. I have tried disconnecting the exhaust at the turbo down pipe and no difference.
 

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Discussion Starter #14
I found a guy that's meeting with me Tuesday night to test my air flow meters in his car. I'm also gonna change my fuel pump see if there's a difference. This no code problem is annoying.
 

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Discussion Starter #16
I don't have the original sensor that came with the car. The box with white around it right ?
 

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Discussion Starter #18
yeah that's what it's suppose to be but I only have ones ending in 42011 and 42010.....And all of the guys in my area who part supra's out don't have one ending in 42020, they only have the lexus ones....it's frustrating. If i send one ending in 42011 or 42010 out to get rebuilt i'm still gonna end up with a lexus AFM lol Argggg...... =(
 

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Discussion Starter #20 (Edited)
So i guess that's my problem then because, I'm not throwing any codes and everything set right...now it's just how do i get a hold of one, Toyota wants 1800 dollars.....for the only one they have. ebay has nothing and our local automotive store (Lordco) doesn't sell them only takes them and sends them off for a rebuild.

By the way thanks for all the help everyone especially bassjunkiens5
 
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