Starts for a second and dies
#1
Starts for a second and dies
So I replaced the head, timing chain, water pump, and oil pump. I have triple checked the timing and it is good. The spark plugs are wet with fuel. It will start up for a second and dies.
I bought it for 1500 and knew it had a bad head. Now I am stuck so any advice would be appreciated.
I bought it for 1500 and knew it had a bad head. Now I am stuck so any advice would be appreciated.
#3
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This is a classic COR/VAF problem. The fuel pump starts with the STArt signal, but it keeps running only if air is being sucked through the VAF (so if you get in a crash that breaks a fuel line, the pump will stop!)
It's very easy to diagnose (long before you start "swapping" out parts). First, you do have all of the air intake plumbing connected, don't you? Jumper FP to B+ in the diagnostic connector. With key-on, the pump will run. If the truck runs now, you've located the problem. (And don't drive around with the jumper in -- you want that pump to stop as soon as the engine stops sucking air.)
It's very easy to diagnose (long before you start "swapping" out parts). First, you do have all of the air intake plumbing connected, don't you? Jumper FP to B+ in the diagnostic connector. With key-on, the pump will run. If the truck runs now, you've located the problem. (And don't drive around with the jumper in -- you want that pump to stop as soon as the engine stops sucking air.)
#4
So I figured it out. Even though I am embarrassed to say. So I did not hook up the intake tubing. Once I did it fired right up. So the afm caused it not to start. Now I have the problem of the tps reving up to 3k rpm back down to 750. I need to figure out if it is a vacuum leak or a sensor telling it to rev up. All in all a pretty good guam buy for 1500.
#5
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So I figured it out. Even though I am embarrassed to say. So I did not hook up the intake tubing. Once I did it fired right up. So the afm caused it not to start. Now I have the problem of the tps reving up to 3k rpm back down to 750. I need to figure out if it is a vacuum leak or a sensor telling it to rev up. All in all a pretty good guam buy for 1500.
Check you throttle cable. With the truck off, press the accelerator pedal and watch the throttle body move. If it sticks or returns back slowly, it's dirty. Remove the cable from the pedal and throttle body (and bracket from firewall in engine bay) and clean & lube up that sucker.
If you have an auto or cruise control, check those ones too.
If that doesn't fix it, your TPS probably need adjustment. If it will not adjust (or out of spec in regard to reistance) replace.
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