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TBI won't fire up

Wes Harden said:
yeah it won't have bolt bosses for a tbi coil
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I knew that, just wondering what others did who converted. I'm leaning toward nutserts on the firewall at the moment.

I seem to recall there was some complication with swapping to a TBI intake from a carb application, but I'd consider it, to get rid of the adapter.
 
It looks like the bolt pattern doesn't line up with the heads between TBI engines and carb. I'm unable to find any TBI conversion manifolds. So I guess everyone who does a TBI swap uses an adapter?
 
Did the smaller cap allow GM to mount the coil to the intake where they did?

Would that have any impact here?
 
Here's an aftermarket TBI manifold. I only see one bolt hole that might be used for coil mounting. Is that all they had from factory too?

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Just for the record, another higher level diagram. I'm curious, anyone know what vehicles/years had large cap vs. small cap? Lots of these CK diagrams seem to indicate large coil-in-cap.

1707579155581.png
 
The 86 3.8l Buick 6v had the coil in cap.
I do not remember seeing this in trucks.
The first tbi big blocks had a tbi adapter to q jet from GM 88ish, at least in p vans.
Yes I don't imagine much call for non vortec tbi intake any more.
I think the nutzert idea will work
 
Why do you suppose that schematic left off the distributor to coil connection? It makes me think it's coil-in-cap, but maybe not.
 
I don’t know where that diagram is from but I had a ‘89 c2500 that definitely was not coil in cap. It was small distributor with separate coil.
 
Doesn't surprise me the dia is not accurate. Many factory instructor designed troubleshooting diagnostics problems around errors the service mananul, there was no shortage of lessons
 
I
Wes Harden said:
76 is when the olds became the corporate motor, Caddy owners got all up in arms say they spending Caddy dollar on an olds engine, then the 4.2 aluminum with dfi came out 82 ish ? in both front and rwd models, and let not forget the 8 6 4 that eventually was modded to just 8. sorry for the High jack
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Had one of those 864 81 Cadillac.
Drove it cross country a couple of times then got to CA and got t boned.
I liked it but it sounded and felt funny running on 4 cylinders, but got 30mpg when on 4
 
Hey guys. Teach me about getting the tang (flat part at bottom) lined up while also getting the timing the way I want. I have the direction marked for the rotor, but if I drop the distributor in at the right angle for that, the tang doesn't line up (it won't seat despite wiggling). I can get it to go in all the way, but only if I start further over and the rotor doesn't come out at the right angle. The tang is for the oil pump? Can I rotate it with a long screwdriver? I could also just rotate the cap to match, but that seems wrong.
 
I us the big craftsman screwdriver to turn the oil pump drive. Iirc the drive is almost parallel to drop the dist with rotor pointing at #1

edit: parallel to crank*
 
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I might get flamed for not reading all the threads but I started at the beginning where it would crank and not start or was intermittent. Somewhere things changed to dist/tbi. This may have nothing to do with your situation but just a data point. I had a similar issue on my 88. Discovered that when I got pissed and just continued to crank it over it would start. Turns out it was a bad fuel pump/oil pressure switch. By cranking it over for a longer duration it allowed oil pressure to build up enough to close the switch and engage the circuits and it would start.
 
Wes Harden said:
@88Silverado, that switch is fuel pump circuit redundancy.
Your fuel pump relay is/was bad. Or the computer wasn't turning it on.
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You are correct, Per my log I changed the pump relay in 05. Remember now had to crank it forever for oil pressure to come up to close a switch to turn on pump. In fact, I think Dorian helped me with that one. Thanks for jogging the memory. Sorry for disrupting the thread...
 
Almost ready to see if it'll start. I'm noticing that the towers on this distributor are shorter than the old one and the boots seem too long for them. The coil wire I got won't stay on the cap because the boot is compressed and pushes it off. Do the small cap distributors require special plug wires? In the pic you can kind of see how the tower on the coil is taller than the ones on the distributor.

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It fired up first try! From what I can tell, EFI wires have different boots. For now I just trimmed down my existing ones. I might get the correct ones just for the fun of it, and maybe a proper length coil wire. I'll tidy up the wires and call it a wrap.

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