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Old 11-17-2016, 09:04 PM   #51
Blessed66
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Re: Throttle body issues

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Originally Posted by Chrispbrown36 View Post
Stabbed the distributor.
Hmm. That's odd because, assuming my information is right, your fuel pump will prime when you turn the key on, but won't actually "pump" until getting a crank signal (from starter), good oil pressure (from sensor, while cranking), hot from relay (key on).

Stabbing the distributor shouldn't be something that energizes/primes the pump in any way. I'd be checking grounds, if I were you. I've been tearing apart my harness and there's a few common grounds (2-3) on the entire harness.
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Old 12-16-2016, 02:48 PM   #52
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Re: Throttle body issues

Did you happen to get this sorted yet. Thanks
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Old 12-16-2016, 05:01 PM   #53
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Re: Throttle body issues

I talked to the guy at the shop today and he is backed up. Can't get the truck in until the 28th. I will keep you posted as best I can. Based on everything I had told him I had tested and changed he was amazed I was still having an issue....so we will see.
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Old 12-16-2016, 09:20 PM   #54
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Re: Throttle body issues

I'm no expert on fuel injection, but if it will start/run when you pour fuel into the throttle body, that tells me all electrical is good including the distributor. It sounds to me like a pinched or clogged fuel line somewhere between the tank and throttle body. I think the fuel pressure would still measure fine with a pinched line, but the volume would plummet and then pressure would drop once it started (like your symptoms). Wondering if maybe damage could have happened to fuel line during your intake/gasket repairs?

Anyway, I'm curious to hear how it turns out. I always liked the 1987's...the only square body with tbi.
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Old 12-16-2016, 09:22 PM   #55
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Re: Throttle body issues

At this point I am ruling nothing out....but it is now in the hands of an expert ha ha.
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Old 12-24-2016, 03:26 AM   #56
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Re: Throttle body issues

This might be of help to you. It's a lot of info and they seem to break down how the tbi functions very clearly.
http://chevythunder.com/fuel%20injec...g%20pg%20a.htm
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Old 12-25-2016, 07:29 AM   #57
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Re: Throttle body issues

Still sounds like the only thing left is some issue with throttle body. You mentioned all you did was install new gaskets, but something is wrong at this point with the fuel delivery. Throttle body and injector area is one of the things you had apart, recheck it. Even if you have to redo what you did.
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Old 01-06-2017, 05:48 PM   #58
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Re: Throttle body issues

The truck is at the shop now. I am hoping that he will call me today and tell me it is back up and going. I think, more than likely, it is something very simple that I just kept overlooking, but we will find out....soon I hope...duck season is getting awfully close to ending and there are divers calling my name!
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Old 01-07-2017, 08:31 AM   #59
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Re: Throttle body issues

I don't see where you ever checked the codes. That is usually the easiest thing to do. I thought that link by plano was going to get you on the right track. Oh well, the mechanic will probably check codes first and go from there.
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Old 01-16-2017, 07:42 PM   #60
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Re: Throttle body issues

It isn't throwing any codes.
A little update for everyone....As of right now the mechanic is stumped. He went back over everything I had (ignition module, distributor, fuel pressure, etc.) and it is all good. He thought he had found an issue with the grounds...fixed it and still nothing. On Saturday he thought he had found a spot in the harness that had been rubbed down that might be causing the issue....not it either. At one point he had no power at the ecm fuse. He resolved that and still no go. He told me today that he was going to pull the new distributor I put in out and try another one. I really thought and hope it was something minor that I had missed and he would quickly find it and fix it. This is pushing me even more toward scrapping the tbi and putting a carb on it.
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Old 01-17-2017, 07:01 PM   #61
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Re: Throttle body issues

Well, it is back up and running. He said that one of the four power wires going into the ecm had broken. He spliced it back together and she fired right up. Took it for a test drive and the lower radiator hose blew out. Took it back fixed the hose, took it out again, and it started overheating. Changed the thermostat and all is well.
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Old 01-17-2017, 11:13 PM   #62
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Re: Throttle body issues

Awesome - I am glad it is finally sorted out, was certainly a head scratcher.
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Old 01-18-2017, 07:13 PM   #63
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Re: Throttle body issues

Well, now a new issues has arisen. It continues to overheat. He said that it rises to 260 (not sure if he based this on the gauge or some other way) and the upper radiator hose stays cold. He questioned whether I had put the intake gaskets on the wrong way. I really don't think I did, but I guess anything is possible. He is going to run a bore scope down it tomorrow and see if he can see anything.
Anyone have any ideas of something else to look at for the issue?
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Old 01-19-2017, 07:22 PM   #64
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Re: Throttle body issues

Drove her home tonight. The idle is back where it should be (it had been idling high, which is why I originally tore into the intake gaskets). Ended up being injectors along with the broken power wire at the ecm. The over heating issue was my fault...apparently I had put the intake gaskets on the wrong way and had the ports blocked.....that won't happen again. He opened them up to get her on the road, so I will have to open it back up eventually and put new intake gaskets on it....again. I feel like a moron for putting the intake gaskets on wrong, but I am glad that the injectors and the ecm were the original issues and not something I had screwed up.
It's nice to have her back. The wife and I had been carpooling for two weeks (since my beater car broke down on me....it is going to a junk yard) and we had had enough of each others company!
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