1987 V20 stall issue

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bpwiles

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Hello all - I did some searching for this in forums and found a few threads that were older but nothing that was useful and was hoping anyone could give this a read and possibly some advice.

1987 V20. 350 crate motor with flat tappet lifters. Lifter in CYL 3 went out so we pulled it apart and upgraded to aluminum heads, new cam and roller lifters - all Edelbrock. Truck starts fine both cold and warm. Idles in park/neutral but when it warms and in drive, will stall when putting it back onto park. To get it started, I pull the air cleaner and then pull the injectors and crank it to burn off excess fuel. Plug the injectors back in and can crank but will stall again so I crank in neutral and it will idle. I can give it gas at that point and put it in drive and all is fine. Nothing in the gauge cluster is stock including warning lights (Autometer gauge cluster) so diagnosing it is Manuel. It's a frame off “rebuild and mod” and has a new gas tank, new fuel lines, new filter, 60859 Edlebrock heads, K08-501-8 Comp Camp (computer controlled), Hurst floor shifter (originally it was a manual but previous owner converted it to an auto TH400 but didn't get the linkage right so I converted it to a floor mounted shifter, Davis Unified Distributor, MSD Blaster Ingnition, new IGK plugs.

Next steps in diagnosis is putting a fuel gauge on it to see what pressure its getting at the TBI and then aTBI rebuild with pressure control valve and idle air valve. Yes, I'm shopping a new EFI that is a next year budget. Also looking into a new chip at a few places.

Any thoughts on what I may be missing?
 
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Ricko1966

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"Nothing in this is stock" means nothing in this is restored. Check the value on the CTS.
 

bpwiles

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"Nothing in this is stock" means nothing in this is restored. Check the value on the CTS.
Thanks for the correction Rick - I’ll be sure to keep that in mind in the future when posting.
"Nothing in this is stock" means nothing in this is restored. Check the value on the CTS.
Thank you Rick for pointing out the errors in my post, I have corrected them.
 

Ricko1966

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Seriously check the value on the CTS if it thinks it's cold it's going to signal the ECM to supply extra fuel.
 
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bucket

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So you are running TBI with a bunch of aftermarket stuff? That right there is an issue... you really need to get a chip burned for your application.

Also, you don't have to unplug the injectors. Just put the pedal to the floor while cranking. The ECM should not fire the injectors in that situation.
 

bpwiles

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So you are running TBI with a bunch of aftermarket stuff? That right there is an issue... you really need to get a chip burned for your application.

Also, you don't have to unplug the injectors. Just put the pedal to the floor while cranking. The ECM should not fire the injectors in that situation.M

So you are running TBI with a bunch of aftermarket stuff? That right there is an issue... you really need to get a chip burned for your application.

Also, you don't have to unplug the injectors. Just put the pedal to the floor while cranking. The ECM should not fire the injectors in that situation.
Yeah - looking at EFI upgrades but budget says next year. I do have some q’s out on getting a new chip last week so thanks for that recommendation. I’ll try the full pedal at start tip next time it does it. Thanks for the info!
 

Ricko1966

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Also find the wire for the check engine light, hook a test light to it then short terminals a and b together at the ALDL. read the flash diagnostics. Might save you some time.
 

bucket

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Brian at Tbichips.com can burn a chip for you. Yeah, it's mail-order and may take a couple trials, but overall it will work better than dealing with an unhappy TBI setup that doesn't work well with heads and cam. If your cam is too wild for TBI, he will tell you from the start too.
 

bpwiles

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Brian at Tbichips.com can burn a chip for you. Yeah, it's mail-order and may take a couple trials, but overall it will work better than dealing with an unhappy TBI setup that doesn't work well with heads and cam. If your cam is too wild for TBI, he will tell you from the start too.
Thank you bucket! I’ll call them Monday. Appreciate the recommendation.
 

gmbellew

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in my opinion, keeping TBI mostly stock or close enough to stock to use the stock tune, unless you plan to tune yourself, is the best idea.
 

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