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Discussion Starter · #1 ·
I'm hitting fuel cut between 4.5 and 6 psi. My boost used to run between 8 and maybe 10 psi, now the most I get is 6 to 8 and sometimes it just starts hitting fuel cut all the time, sometimes it goes away for a while. Like for a few days/weeks it will give me problems, then it works ok for a few days/weeks. Is there a boost pressure sensor maybe going bad? Yesterday I was in a hurry and couldnt go over 130 mph because it kept hitting fuel cut, then it started running pretty bad like it was missing any time I gave it gas. I slowed down to like 80 or 90, and as I came into town and slowed down to 40 or so, it seemed to be running better. I got on it a few times, ran ok other than still hitting fuel cut. If you guys have any ideas, I'd appreciate some help. Thanks.
 

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I heart 80's Toyota's
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91SUPRA-B said:
Yesterday I was in a hurry and couldnt go over 130 mph because it kept hitting fuel cut

Maybe thats a good thing??

Anyways, does the check engine light come on when it hits cut?
 

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Did you check the code?

I was hitting fuel cut to early in my turbo truck.... was getting a code for a bad AFM when it would hit fuel cut... sure enough, I had a bad AFM
 

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Discussion Starter · #7 ·
I'll go check the codes. Yeah the light comes on for a few seconds. Have already been suspecting a boost leak, had one before but got it taken care of, may have another. Also, used to think I was having afm problems, and I am using a k&n which apparently the oil causes afm problems. They seemed to go away, but maybe afm problem is back. I want an apexi filter to help get rid of this problem. Will the afm from an 87T work on a 91T? Thanks for the help guys.
 

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Discussion Starter · #8 ·
Did your check engine light stay on when you set a code for a bad afm? Mine is not staying on, just comes on for a few sec.
 

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91SUPRA-B said:
Did your check engine light stay on when you set a code for a bad afm? Mine is not staying on, just comes on for a few sec.

It would only stay on for a few seconds
 

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Discussion Starter · #10 ·
Had code 34 for abnormal boost pressure. It says either short in sensor circuit, boost sensor itself, turbo, or ECU would be the problem. Where is the sensor on the engine guys?
 

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91SUPRA-B said:
Had code 34 for abnormal boost pressure. It says either short in sensor circuit, boost sensor itself, turbo, or ECU would be the problem. Where is the sensor on the engine guys?
That code is stored if you hit fuel cut.

Check for boost leaks, it most certainly could be your problem.
 

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Discussion Starter · #12 ·
You guys were right, boost leak. I was checking things, and looked like the hose right out of the turbo was split just past the clamp that holds it to the turbo. I took it off and damn, it was almost split in 2 pieces. I dont know how it was getting any boost at all. So my question now is, Will that particular hose from an 87 fit on a 91? I have heard some of the hoses, or maybe the intercooler are different. Also, do you think it would still reach ok if I cut about an inch and a half off of it? Thanks again fellas.
 

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Discussion Starter · #13 ·
Well so I decided to rob the hose off the 87 parts car, got down to it and was ready to take the clamp off, and looked like it was split too. And even if it wasnt, I didnt feel like it was worth the trouble to take it off and find out, wouldnt be much different than cutting the other hose down and trying it. So thats what I did, getting ready to go for a test drive...
 
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