fuel cut question

jdmahmed

New Member
Jan 8, 2006
6
0
0
Cali
Hi, and merry xmas folks. I have an 89 turbo, with a speed swap (still on auto ecu). I have a 3 inch elbow back system, intake, some IC hardpipes, spearco copy IC, an mbc, and an aftermarket boost gauge. Under partial throttle, I can hit 10 psi of boost. Under partial, and gradually going to wot, I can still hit 10 psi. However, if I go wot in 2nd gear, then shift to 3rd, as soon as Im on the throttle again at wot, it will hit fuel cut. It will hit fuel cut before my gauge shows 6 psi. Seems like it only hits fuel cut under wot in any gear after 2nd. The only codes I have present are 34 and 71 (i think this is because its a cali ecu on an engine with no egr temp sensor?). I have gone over all the couplers, hoses, vaccuum lines. I have the TPS adjusted according to the tsrm. Im out of ideas.
 

clifftrail

New Member
Jun 19, 2005
128
0
0
Abq
Do you have anyway to adjust the fuel? Its probably dumping too much fuel in causing it to trigger fuel cut when you floor it, so if you can lean it out a little it would probably get you past that.
 

MassSupra89

Almost done.
Nov 3, 2005
1,707
0
0
MA
clifftrail said:
Do you have anyway to adjust the fuel? Its probably dumping too much fuel in causing it to trigger fuel cut when you floor it, so if you can lean it out a little it would probably get you past that.

"Fuel cut" is actually when too much air is entering and the car cannot provide enough fuel. A lean mixture is the problem, not the solution.

DO NOT pull fuel even though it seems you have no way of doing this anyway.
Fuel cut is to keep you from running lean, and making engine go Kaboom.
 

122578

just takes time
Dec 16, 2005
39
0
0
n.c.
jdmahmed said:
Hi, and merry xmas folks. I have an 89 turbo, with a speed swap (still on auto ecu). I have a 3 inch elbow back system, intake, some IC hardpipes, spearco copy IC, an mbc, and an aftermarket boost gauge. Under partial throttle, I can hit 10 psi of boost. Under partial, and gradually going to wot, I can still hit 10 psi. However, if I go wot in 2nd gear, then shift to 3rd, as soon as Im on the throttle again at wot, it will hit fuel cut. It will hit fuel cut before my gauge shows 6 psi. Seems like it only hits fuel cut under wot in any gear after 2nd. The only codes I have present are 34 and 71 (i think this is because its a cali ecu on an engine with no egr temp sensor?). I have gone over all the couplers, hoses, vaccuum lines. I have the TPS adjusted according to the tsrm. Im out of ideas.


merry christmas! i am having the same problem as you but in 2nd gear only. i found that when i reset the maf it stops temporarily not sure y but now pursuing a fuel problem so if i find anything 4sure i'll let u know.
 

clifftrail

New Member
Jun 19, 2005
128
0
0
Abq
Save yourself some trouble and take it to a dyno, and have a wideband monitor it while you make some pulls. That will tell you what is going on with the fuel. GL.
 
Last edited: