84 350 TBI conversion too lean, suggestions?
#1
84 350 TBI conversion too lean, suggestions?
I converted an stock 84 carbed 350 in my jeep to TBI. I used an 88 1500 pickup with a 350 as the donor. I have it running but it is really lean. I have checked the fuel pressure, 11 psi all the time, timing, spark gaps, changed to heated o2 sensor, everything I can think of. Currently the only flags in winaldl are lean o2. It cranks up will idle a little high, go to closed loop for a few seconds and then kick out of closed loop. The blm stays around 135. the o2 sensor values look like they are correct, around .2. THe rest of the sensors look like they are pretty normal. THere are no vacuum leaks. I have the stock chip and have the knock circuit grounded and p/n switch grounded. I thought the 2 motors curves would have been closer than the way this is running, but is it possible that they are not and I just need a new chip? I would appreciate someones help.
THanks
Brook
THanks
Brook
#2
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Re: 84 350 TBI conversion too lean, suggestions?
Beardb
Welcome to thirdgen.org
Based on your description I have a question - why did you ground your ESC module output line?? Please confirm if it is the case. I assume that you have ECM 7747 with a typical 350 BIN (which one).
Under normal conditions ESC module output is around 9 volts unless there is an engine ping (it goes low). Run WinALDL - check knock counts - with grounded input you'll see lots knock counts. This may explain lean condition - and retarded timing.
Also check for exhaust leaks (for example AIR injection valve is leaking, etc)
//RF
Welcome to thirdgen.org
Based on your description I have a question - why did you ground your ESC module output line?? Please confirm if it is the case. I assume that you have ECM 7747 with a typical 350 BIN (which one).
Under normal conditions ESC module output is around 9 volts unless there is an engine ping (it goes low). Run WinALDL - check knock counts - with grounded input you'll see lots knock counts. This may explain lean condition - and retarded timing.
Also check for exhaust leaks (for example AIR injection valve is leaking, etc)
//RF
Last edited by RFmaster; 07-30-2007 at 12:04 AM. Reason: add new
#3
Re: 84 350 TBI conversion too lean, suggestions?
the only thing grounded is the knock circuit to prevent it from retarding. I read on
numerous places to ground that pin if you did not want to run the knock sensor. the ecm is 7747 and stock 350 bin. do you think there would be that much difference between gen two and three 350s? thaks for the response.
numerous places to ground that pin if you did not want to run the knock sensor. the ecm is 7747 and stock 350 bin. do you think there would be that much difference between gen two and three 350s? thaks for the response.
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