TahoeInOhio
New Member
- Joined
- May 20, 2013
- Messages
- 3
- Reaction score
- 0
Hi All,
I've recently laid purchase to a 97 tahoe that looks good and runs bad.
It ran very rough, was stalling, and was difficult to start. It was throwing codes for all O2 sensors and MAF. I cleaned the maf, and tightened the screws for the air intake silencer box that says "Vortec" on it which was very loose. I also have found 5 of 8 sparkplug wires were not clicked on properly.
After fixing those issues, I reset the computer, have been cruising the truck around town, and so far no codes have come back. The truck runs good at idle now, and up to about half throttle it runs OK as well, but giving it WOT makes the engine bog down.
I tested the fuel pressure. Its 50-55 psi and supposed to be 60-66 psi. I changed the fuel filter. That made no difference. When the fuel pump is priming, it runs up over 50, then drops down to zero almost immediately. Is this suspect fuel pump or fpr or something else?
The distributor cap seems to be OK, but the plastic ears on the distributor that the screws are supposed to screw into are half broken off, so I can't tighten the cap down as well as I would like. But it doesn't seem to wiggle up or down or sideways.
The last issue that I've found is that around the plug for the fuel injector spider, on top of the upper intake manifold, the plastic is chewed up, like someone pried around the plug with a big old screw driver. I don't detect any vacuum leaks spraying around it with TB cleaner while it idles, but I have noticed that when I rev the engine, the piece that the plug goes into physically moves up when I open the throttle, and moves down when the throttle is closed. I've no experience with Vortec 350's, but that doesn't seem right.
So... where do I start? What do you wager the problem is? :help:
I've recently laid purchase to a 97 tahoe that looks good and runs bad.
It ran very rough, was stalling, and was difficult to start. It was throwing codes for all O2 sensors and MAF. I cleaned the maf, and tightened the screws for the air intake silencer box that says "Vortec" on it which was very loose. I also have found 5 of 8 sparkplug wires were not clicked on properly. After fixing those issues, I reset the computer, have been cruising the truck around town, and so far no codes have come back. The truck runs good at idle now, and up to about half throttle it runs OK as well, but giving it WOT makes the engine bog down.
I tested the fuel pressure. Its 50-55 psi and supposed to be 60-66 psi. I changed the fuel filter. That made no difference. When the fuel pump is priming, it runs up over 50, then drops down to zero almost immediately. Is this suspect fuel pump or fpr or something else?
The distributor cap seems to be OK, but the plastic ears on the distributor that the screws are supposed to screw into are half broken off, so I can't tighten the cap down as well as I would like. But it doesn't seem to wiggle up or down or sideways.
The last issue that I've found is that around the plug for the fuel injector spider, on top of the upper intake manifold, the plastic is chewed up, like someone pried around the plug with a big old screw driver. I don't detect any vacuum leaks spraying around it with TB cleaner while it idles, but I have noticed that when I rev the engine, the piece that the plug goes into physically moves up when I open the throttle, and moves down when the throttle is closed. I've no experience with Vortec 350's, but that doesn't seem right.
So... where do I start? What do you wager the problem is? :help:
