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throttle killing engine help???

C

CromeY90

NAXJA Forum User
Location
b.c
just finished doing a engine swap everything went awsome started right up now just have to tweak everything like my throttle if u press down quick it stutters engine almost dies if it dosent fully die but if u slowly press down its fine and it idles at like 250 to 500 rpm is that to low any help on the throttle delay and killing the engine would be awsome would really like to get this figured out
 
stumble after quick throttle opening will probably be caused by either a lean mixture (ecu unable to compensate for excess air quick enough) or timing slightly off (likely no more than one tooth)

I'd verify that all vacuum lines are connected and the intake is tight, then I'd re-time the distributor. Vacuum lines that are suspect (all are important, but some more-so) are the one to the MAP and the ones directly off the intake as they are big enough to reek havoc on mixture ratio.
 
we checked all that but who knows maybe missed something not sure it was a long weekend as i just finished the swap early this evening so ill havta fully investigate all those again
 
Idle should be at 700-750 RPM. The IAC should maintain that. The IAC is responsible for the idle as well as performing part of the old carb "transition circuit" function, as in transitioning from idle to throttle.

You need to check the idle with the engine and transmission fully warmed up, after about 20 minutes of operation. Check the idle in D, you will need someone to help you by sitting in the driver's seat, parking brake on and service brakes applied. Don't rely on the IP tach, use a separate tach. If the idle is wrong, you will need to find out why--TPS/IAC/running rich, or some combination of those.
 
Shorty said:
stumble after quick throttle opening will probably be caused by either a lean mixture (ecu unable to compensate for excess air quick enough) or timing slightly off (likely no more than one tooth)

I'd verify that all vacuum lines are connected and the intake is tight, then I'd re-time the distributor. Vacuum lines that are suspect (all are important, but some more-so) are the one to the MAP and the ones directly off the intake as they are big enough to reek havoc on mixture ratio.
Click to expand...

X2 on all this
re-index the dist, check the vac lines, check the IAC and clean it while you're there, and make sure the TPS is adjusted properly, i believe its .8 volts when its set correctly. To do this loosen the bolts to the tps, hook up your Volt meter, and probe the connector. set to .8V when checking across A and C connectors. you have to rotate the TPS. when .8 volts is reached hold it there, and re-tighten.
 
thanks for all the advice i will try all these as soon as i get a chance hope one works and if anyone else has anything else let me know would really like to get this fixed and thanks again to all who have replied so far:)
 
how do yoiu adjust it anyone got a pic of where i adjust it because my maual is retarted only shows a 96 model
 
When was the last time you changed your fuel filter? Any other issues that might be thought of as unrelated?
 
well fixed this issue today it was a combination of things but gotter fixed thanks to everyone who suggested something because it all got it fixed thanks again:D
 
well one thing was i found that the hose from the throttle body to the air box had 4 nice slash holes replaced that made a lil better changed the iac fixed the idle a bit then checked the tps and it wasnt at .8v and adjusting it wouldnt make it go up any highe then .47 so replaced it and set it to .8v and wa la dosnt wanna stall when you put the pedal to the metal :D
 
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