1999 Chevy Tahoe 4x4 Crank - Will Not Start - SOLVED

Thanks, that helps. I see it now in the 1st edition C/K book but they deleted it in the 2nd. But mine still has the blurb about the oil pressure switch powering the pump. I guess the revision made sense to someone at the time, lol.

My 99 burb needed 3 new fuel pumps before I got one to work properly. When it didn’t start up before the new pumps I’d give it a whack on the fuel tank with a 2x4 and the pump would start right up. I had a shop do the pumps and we found that redline pumps made the gas gauge wildly inaccurate and the delphi worked out of the box.

Coveman said:

My 99 burb needed 3 new fuel pumps before I got one to work properly. When it didn’t start up before the new pumps I’d give it a whack on the fuel tank with a 2x4 and the pump would start right up. I had a shop do the pumps and we found that redline pumps made the gas gauge wildly inaccurate and the delphi worked out of the box.

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Agreed that the brand of pump matters. I had similar issues on my '96 Suburban. OEM GM or Delphi is what I would try to get. There may be other good ones out there also. Unfortunately, AC Delco doesn't mean much these days. Might be good or not.

Just wanted to provide an update.

The truck has started and ran since my original post. It does seem that the problem is getting much worse though. I only got it to start 3 times before it did not start for 12 hours+. Again, the truck used to give me 5-6 starts before it would just sit and crank. I could swing the key back and forth for 5-10 minutes before I would hear the fuel pump prime, and it would fire up and repeat the whole process over. Not the case anymore.

Went ahead and just purchased a GM Genuine (ACDelco) oil pressure switch and put it in on Sunday. Did not seem to fix the problem. It did seem to normalize my oil pressure gauge a bit. Before it was a little jumpy/glitchy. Could be a placebo effect, but hey I'll take it. Lol

Got the truck to start up yesterday morning, so I went ahead and drove it straight down to a family friend who knows vehicles and owns his own shop. He is going to look into the electrical aspect of the fuel pump. He was also suspecting the spider injector. If the fuel pump electrically checks out. He said he will be removing the intake today to determine if the spider needs replaced.

I noticed this time driving it, upon acceleration it had the slightest hesitation when keeping a steady throttle. I was going down the highway around 45-50 MPH, and the truck felt like it had the slightest bit of bog in it. I could even see my RPM's ever so slightly bogging down when I would feel it.

I will keep this thread updated as the information comes. Hopefully we can finally put this problem to rest. I love this truck and just want to trust it again.

If the pump isn't running the spider injector has nothing to do with it. The oil pressure switch doesn't come into play when you turn the key to prime the system, at least it helped your gauge. I guess you never monitored voltage at the pump or ground. Did you try activating the pump at the test lead shown in the wiring diagram?

Eman85 said:

If the pump isn't running the spider injector has nothing to do with it. The oil pressure switch doesn't come into play when you turn the key to prime the system, at least it helped your gauge. I guess you never monitored voltage at the pump or ground. Did you try activating the pump at the test lead shown in the wiring diagram?

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I did not. I shared all the wiring diagram information with the mechanic, and he was going to look into it. Been waiting since yesterday to hear back.

Once I get any information, I will update this thread.

OBSTheBest said:

I did not. I shared all the wiring diagram information with the mechanic, and he was going to look into it. Been waiting since yesterday to hear back.

Once I get any information, I will update this thread.

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Fuel pressure is low when running. Your mechanic should be able to decide whether that is a burned connector/wiring, bad ground or bad pump. A look at the computer connector for relay to check for corrosion/water/green stuff in there a possibility also.

exp500 said:

Fuel pressure is low when running. Your mechanic should be able to decide whether that is a burned connector/wiring, bad ground or bad pump. A look at the computer connector for relay to check for corrosion/water/green stuff in there a possibility also.

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Thank you for this! I am going to suggest this to him, even if he should already know. I still have not got any word from him today, so I may give him a shout on my way home from work. Thanks again!

SOLVED - Turns out the Spider Injector was bad.

Purchased the GM Genuine MPFI Spider for $480 on CarID with GM Genuine gaskets, and the old man charged me $250 to put it all in. Took about a week to arrive from UPS and the old family friend had the truck done and back to me the next day.

Have been driving it since Thursday without any issues. Fuel pump primes at the first turn of the key, and the truck starts with every swing of the key, instantaneous!

Boy, it feels good to finally have the truck in good running shape again!

Thank y'all again for all your knowledgeable feedback on this forum!

OBSTheBest said:

SOLVED - Turns out the Spider Injector was bad.

Purchased the GM Genuine MPFI Spider for $480 on CarID with GM Genuine gaskets, and the old man charged me $250 to put it all in. Took about a week to arrive from UPS and the old family friend had the truck done and back to me the next day.

Have been driving it since Thursday without any issues. Fuel pump primes at the first turn of the key, and the truck starts with every swing of the key, instantaneous!

Boy, it feels good to finally have the truck in good running shape again!

Thank y'all again for all your knowledgeable feedback on this forum!

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Glad you got it fixed!
Please EDIT title page, add "SOLVED". Thanks