missfire at idle and steady cruise

[justin90gsx]

i just put a new motor in with 272 cams, springs, retainers, ss valves, 3 angle valve job, 2g pistons on 1g rods, arps throughout, cometic head gasket, so new anything on the motor
and 850's, stg 3 dsm chip set at 850's, afpr, full intake and frontmount, full exhaust, cop setup, gm 3 inch w/ translator.
the timing marks are on
timing is set at +5*
so it misses at idle and my wideband reads at 17.5 and some times more and some times it runs fine and go's to 13 or so.
and it misses and jerks at a steady cruise as well and reads at like 15
but when i give it gas or WOT its fine and its at 11.1 and hauls a$$ ????

so i swapped to stock injectors, mafs and ecu and still does it
so i ordered some new plugs the 7es plugs
unpluged one coil on plug at a time and runs worse when i do.
used a noid light to see if i was getting pulse from the injector clips and their fine

i dont know what to do now
can someone please help!!!! thanks!!!

 

[innocenttalon]

Sounds like my car before, except mines would miss even at WOT, turns out it was the CAS thats bad. Wont hurt to check it.

 

[justin90gsx]

the throtel body and the cas is the only original parts on the motor
but ill try a cas!

 

[DSMified92]

wow guy that retty much the exact same motor that im building for my 90 awd talon ....i hope mine doesnt do that to wel best of luck to u and yea my nt 92 gs i had with the 4g in it did the same thing and it was completly stock just a real slight miss that you could bearly hear at idle and u couldnt cruise round town cause it was real jerky like it was stubbling

 

[justin90gsx]

any other suggestions?

 

[shaunallenallen]

Justin have you checked your isc unit or your biss. i know i sound stupid but its worth to ask.

 

[justin90gsx]

i have a new seal on my biss and no i have not checked mt isc

 

[justin90gsx]

where should my a/f ratios be on my wideband during idle, steady cruise, mid and wot?
any help would be appreciated!

 

[boosted86]

where should my a/f ratios be on my wideband during idle, steady cruise, mid and wot?
any help would be appreciated!

closed loop ( idle, cruise) operation should return a value on your wideband of 14.7:1 ( stoich) as long as your o2 sensor is functioning properly. at wot your wide band should read what you tune to. generally anywhere between 10.0:1 - 11.8:1

 

[Deuce_three]

hmm. you sure your timing is set right? at wot my car running between 10.9-11.4. whats your loggs?