fuel cut when making any boost at all....

[itsjonnyhodge]

so ive read around and asked a few people they have said its the knock sensor.
i havent seen anyone say when they make boost the CEL comes on then goes off...

it hits fuel cut when it makes more than 2psi, cel comes on, then i left off gas, and it goes away. if it is the knock sensor the wire itself needs replacing, correct?

any advice will help.

thanks

 

[GrimJack]

Sounds like a boost leak to me. Have you checked the engine codes?

 

[itsjonnyhodge]

yeah, everything is fine, it runs and drives normal without boost. and i havent check the code.

i picked this car up about a month ago and havent had the time to fuss with it

 

[RTtim]

I would say boost leak, the exact same thing was happening to my car not to long ago.

 

[itsjonnyhodge]

I'm getting a code 51, 12, and 34...

 

[hvyman]

Moved to the 7mgte section.

34 is fuel cut meaning you have a boost leak.

51 is tps or if you have no ac and you pressed the ac button.

12 is cps or starter circuit

http://www.cygnusx1.net/Supra/TechTips/engine_error_codes.aspx

You can pull off the intercooler piping and drive around no problem as long as you dont boost and the afm is hooked up.

 

[itsjonnyhodge]

Moved to the 7mgte section.

34 is fuel cut meaning you have a boost leak.

51 is tps or if you have no ac and you pressed the ac button.

12 is cps or starter circuit

http://www.cygnusx1.net/Supra/TechTips/engine_error_codes.aspx

You can pull off the intercooler piping and drive around no problem as long as you dont boost and the afm is hooked up.

i hope that is the problem. as soon as it cools off outside im going to go look at everything.

and the starter circut, does that need to be tested to see if it has bad connection?

 

[hvyman]

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=48


Has to do with the blue or black wire from the cps to the ecu. COuld be cps itself as well.

 

[gsxr141]

try tightening ALL the intercooler, and intake hose clamps first.

 

[GrimJack]

If it still has stock intercooler / intake piping, I expect both the accordion hose pre-turbo AND the charge pipe off the bottom of the turbo will have big cracks in 'em. I have yet to see a car with any real mileage on it where those pieces are in good shape unless they've already been replaced.

 

[itsjonnyhodge]

car has hard pipes with fmic, a knock off tial bov. i pulled all pipes, and couplers and found no tears or holes in any. ran out of sunlight so im going to put it back together tomorrow morning. after that im going to look at all vacuum lines and check there. other than that i have to look at the cps.

after that im not sure what else can be causing it. possibly afm?

 

[hvyman]

Its a boost leak. Just because there are no holes doesnt mean there isnt a leak somewhere. Best bet is to find a way to pressurize the pipes and run soapy water over them. Or if you can smoke the pipes so smoke comes out of the holes.

 

[RTtim]

Boost leak. Make a boost leak tester or buy one and test for boost leak before you go digging into your car looking for something that might not be there.

I just went thru the same problem you are having right and it was boost leak even tho all my couplers looked good they just weren't sealing against the pipe.

 

[northwestsupra]

been said a lot of times but i will chime in... boost leak