1998 Chevy Silverado 4x4 Starts then Dies
#1
1998 Chevy Silverado 4x4 Starts then Dies
Hello
I acquired a 1998 Silverado 3 door ½ ton 4x4 5.7l Vortec V8 with approx 224k on it. He said all it needed was a flex plate and it would run fine. Well he was in error, the engine was froze up. After a week of soaking the rings in trans fluid and kerosene I freed it up by hand then turned it over with the starter after putting in a new flex plate. Now here is the problem, it starts then dies starts and dies, and sounds like a rod knock .Here is what has been replaced.
New flex plate
New starter
New fuel filter
New fuel pump relay
New oil pressure switch
New 12v battery
Here is what has been checked.
Drawdown test 60-65lbs holds at 65 then drops to 60 after crank
Check fuel pump was pulled and cleaned, not replaced, can hear at prime
Iac pulled and cleaned
Air cleaner pulled and cleaned (K&N)
Check security light flashes at bulb check, then goes out
Check fuses all good
Checked pulse rate (Noid light) all injectors light up at crank
Checked cap and rotor, not bad, cleaned them up like new
Checked with OBDII scanner, no codes
Still the same thing ,starts and dies after you release the key, it will stay running if you feed it gas from a spray bottle. I am using a newer key.
I am stumped I am an old school wrench poor and would like to get it at least running even if it does have a rod knock, sounds like screeching more than a rod knock. Any help would be appreciated.
Regards
I acquired a 1998 Silverado 3 door ½ ton 4x4 5.7l Vortec V8 with approx 224k on it. He said all it needed was a flex plate and it would run fine. Well he was in error, the engine was froze up. After a week of soaking the rings in trans fluid and kerosene I freed it up by hand then turned it over with the starter after putting in a new flex plate. Now here is the problem, it starts then dies starts and dies, and sounds like a rod knock .Here is what has been replaced.
New flex plate
New starter
New fuel filter
New fuel pump relay
New oil pressure switch
New 12v battery
Here is what has been checked.
Drawdown test 60-65lbs holds at 65 then drops to 60 after crank
Check fuel pump was pulled and cleaned, not replaced, can hear at prime
Iac pulled and cleaned
Air cleaner pulled and cleaned (K&N)
Check security light flashes at bulb check, then goes out
Check fuses all good
Checked pulse rate (Noid light) all injectors light up at crank
Checked cap and rotor, not bad, cleaned them up like new
Checked with OBDII scanner, no codes
Still the same thing ,starts and dies after you release the key, it will stay running if you feed it gas from a spray bottle. I am using a newer key.
I am stumped I am an old school wrench poor and would like to get it at least running even if it does have a rod knock, sounds like screeching more than a rod knock. Any help would be appreciated.
Regards
#2
Anything on the serpentine drive system that's seized causing extreme engine drag? Maybe too much internal engine drag to keep running?
I'd start by figuring out if the injectors are spraying .. this is a vortec engine, right?
I'd start by figuring out if the injectors are spraying .. this is a vortec engine, right?
#3
This is a 98 Vortec 350 with the spider assembly and poppet valves. A noid light was used to test injectors it flashed at crank on all cylinder's. The serpentine belt was removed to test it, nothing external was causing drag. The engine starts then dies when the key is released. Relearn was done 15min on then off then another 15mi on then off. The passlock system, when key is turned security light flashes 3 times then goes out for bulb check. Tried ths also.
Regards
Regards
Last edited by Old Wrench; 04-01-2014 at 09:28 AM.
#4
What I'm saying is maybe the injectors are plugged up. I mean verify that the're spraying - you've verified that they're getting the injector pulse signal from the computer, but I mean physically pull the spider and pull all the poppets out and crank it and see if they spray.
If you have a scanner handy, maybe check to see if you have your crank signal going to the ECM, and check to see if your spark timing is way out. Do you know that stabbing the distributor on these vortec engines isn't like stabbing an oldschool distributor? Maybe your timing's off because the distributor isn't quite right.
If you have a scanner handy, maybe check to see if you have your crank signal going to the ECM, and check to see if your spark timing is way out. Do you know that stabbing the distributor on these vortec engines isn't like stabbing an oldschool distributor? Maybe your timing's off because the distributor isn't quite right.
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