TBI Problem - Any Ideas?

John - I looked at the web site that AFI has, I think I see the problem, the no ignition option you purchased has literally NO TIMING controls. I think the kit was targeted to someone who is using thier vacume controlled distributor, my guess is he has removed anything to do with timing controls. As such it will throw things way out of whack..

I think your fuel is sufficient at this point to run the motor, 8-11 is good, thats in line with the stock regulator setting.

Here is what I think you need to do....
Swap your old harness and ESC (Spark Control) back on and I bet it will run. (as it did for the previous owner). Assuming you get there, we can then repin you harness to add back on the EST. Its only a few wires.
 
not to hi jack your thread, but I have a similar issue with a 92 blazer I just put a engine in. when cold it runs decent but when it gets to temp. starts running rich and fouling plugs.
 
:kaioken:

Latest in the saga. Hooked the stock harness up after several hours of tracing wires etc. only to experience the same problem. Engine will fire and run for 15-30 seconds. As long as I give it throttle or spray starting fluid in the TB it will continue to run. If I leave it alone it will die out in 15 seconds or so. Injectors seem to be spraying a nice pattern but it seems to me to be a fuel issue? Getting 8-10 psi on the fuel pressure gauge. Frustrating for sure however I will continue to play with it.
 
Gas works just as good as starter fluid. Blocking off the return line has no affect so according to what I can find out that elimatates the regulator? Just not getting enough gas?
 
Good vacuum, 20hg at idle, when I can get it to idle :) TPS and MAP test good. Crappy pic of fuel regulator housing. Should it be bent like this?

 
thats fine, thats the brute force way to make your refulator adjustable.. There should be a matching tab thats part of the flat washer part thats inside, it sticks out through that slot to keep it from spinning so the factory can do the initial adjustment. Then they solder or other wise make it so you cant (easily) adjust it again.. Pry that back out make it look pretty again....
 
Are you running MAP still or is it pinned programmed out.

Are you running an inline pump or in tank?
I had a problem on my inline wwhere the built in check valve blew out and it would pump plenty of pressure at start up but as soon as the system got full it would vacuum back through and die out. That is not as likely in your case you still see fuel spraying, but just another thought.
 
John, your luck must be rubbing off on me. My YJ with the CMPI Vortec won't run now. I parked it after the Feb. ride waiting to replace the broken motor mount. Brand new Optima lost charge, so I charged it. Now it will turn over and sputter for a couple of seconds before dying. Maybe we need a little prayer session!!!
 
If it were me Id be chasing air/fuel issues or timing issues.
Big help, right?

I didnt go back and read the whole thing , but has it thrown any codes?
Is CEL illuminated (even if you dont run one, which with TBI you should IMHO)
If you unplug O2 does it act exacctly the same?
 
Problem Solved!

Thanks for all the help and ideas. Among lots of other issues, the main problem seems to have been the fuel pump! After researching all the options I went with an external pump for convenience, the Carter P74017, spec'd at 10.3-14 PSI, 23 GPH. Yager stopped by on his way to DPG this afternoon and after fooling with it for awhile we determined that the 8 fluctuating psi it was putting out was not enough. Actually by the time we swapped pumps it was putting out more like 6 PSI. I think it had been going bad and was getting worse, and this was a brand new NAPA pump! We swapped in an E7001, spec'd at 17 PSI, 28 GPH, in tank pump I had laying around and after the computer did some learning we were ideling along fine at a steady 12 PSI! I have learned a lot during all this and have more to learn but I never thought a few PSI would make that much difference in a TBI system! Special thanks to 3DCrawler for some of the most knowledgable and informative TBI info I received along with a good price on the parts!
 
Awesome! Glad to hear you got a handle on it. If you feel like waiting till the semesters over I'll help ya swap it in :).
 
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