about ready to just part it out
07-31-2014, 12:23 PM
#21
Character, assuming your timing is at 20 btdc still.. you should take it down to 10-12 deg. The cold start injector, i'm not asking you to REMOVE the injector, just unplug it. It could be the case that the injector is leaking which will spray way to much fuel into the air stream and cause hesitation, loss of power etc. Or, there could be a short somewhere in the system which tells the ECU to activate the injector after you start it and so on.
07-31-2014, 12:30 PM
#22
I'm in Peoria on 83rd and deer valley. It is set at 10btdc but it will try and kill itself if I full throttle it.
07-31-2014, 12:40 PM
#24
Character, assuming your timing is at 20 btdc still.. you should take it down to 10-12 deg. The cold start injector, i'm not asking you to REMOVE the injector, just unplug it. It could be the case that the injector is leaking which will spray way to much fuel into the air stream and cause hesitation, loss of power etc. Or, there could be a short somewhere in the system which tells the ECU to activate the injector after you start it and so on.
07-31-2014, 01:11 PM
#26
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It could be that the valve timing (not the distributor timing) is off by a tooth. This could have happened when the timing belt was changed. Nothing can compensate for an error like that, and the engine will run and idle like crap. A compression test should give you some information on that - if all cylinders are low you'd want to pull off the timing cover and check the cam timing.
Otherwise, it's likely a sensor that is giving the ECU bad data and causing it to adjust fuel/timing inappropriately for actual conditions. Most likely candidates are
- VAFM
- TPS
Both of these sensors have diagnostic procedures in the FSM using a multimeter. Check here:
http://personal.utulsa.edu/~nathan-b...92volumeai.pdf
and here
http://personal.utulsa.edu/~nathan-b...93throttle.pdf
Otherwise, it's likely a sensor that is giving the ECU bad data and causing it to adjust fuel/timing inappropriately for actual conditions. Most likely candidates are
- VAFM
- TPS
Both of these sensors have diagnostic procedures in the FSM using a multimeter. Check here:
http://personal.utulsa.edu/~nathan-b...92volumeai.pdf
and here
http://personal.utulsa.edu/~nathan-b...93throttle.pdf
07-31-2014, 01:24 PM
#27
okay update on the truck. i set it to factory timing and unplugged the cold start which had no change. then i unplugged the tps and the idle smoothed out but as soon as a full throttle it, you hear a loud knock from the engine and smoke would come out of the exhaust and it would die. im going to take a full day to check the timing myself.
07-31-2014, 02:23 PM
#30
08-03-2014, 06:27 PM
#34
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Possibly. A compression test is pretty easy to run - you just have to pull the plugs - and will tell you a lot about the mechanical health of the engine.
But, given that the idle smoothed out when you unplugged the TPS, I'm guessing the TPS and/or the VAFM are sending bogus signals to the ECU. Check those out before you dig much deeper. 20 minutes with a multimeter and the FSM will tell you a lot.
But, given that the idle smoothed out when you unplugged the TPS, I'm guessing the TPS and/or the VAFM are sending bogus signals to the ECU. Check those out before you dig much deeper. 20 minutes with a multimeter and the FSM will tell you a lot.
08-03-2014, 07:08 PM
#35
Possibly. A compression test is pretty easy to run - you just have to pull the plugs - and will tell you a lot about the mechanical health of the engine.
But, given that the idle smoothed out when you unplugged the TPS, I'm guessing the TPS and/or the VAFM are sending bogus signals to the ECU. Check those out before you dig much deeper. 20 minutes with a multimeter and the FSM will tell you a lot.
But, given that the idle smoothed out when you unplugged the TPS, I'm guessing the TPS and/or the VAFM are sending bogus signals to the ECU. Check those out before you dig much deeper. 20 minutes with a multimeter and the FSM will tell you a lot.
08-03-2014, 10:16 PM
#37
08-04-2014, 06:00 AM
#38
Registered User
Can you post up a video showing start up, and when the symptoms kick in. Maybe some shots of the tach while you experience the problem.
I read that you said you could barely get the dizzy to go down to 10°BTDC? Did you check to see if its off a tooth or two? I have accidentally put mine in once at 180° out, and it would run, but had some oblivious timing issues.
I read that you said you could barely get the dizzy to go down to 10°BTDC? Did you check to see if its off a tooth or two? I have accidentally put mine in once at 180° out, and it would run, but had some oblivious timing issues.
08-04-2014, 09:19 AM
#39
Can you post up a video showing start up, and when the symptoms kick in. Maybe some shots of the tach while you experience the problem.
I read that you said you could barely get the dizzy to go down to 10°BTDC? Did you check to see if its off a tooth or two? I have accidentally put mine in once at 180° out, and it would run, but had some oblivious timing issues.
I read that you said you could barely get the dizzy to go down to 10°BTDC? Did you check to see if its off a tooth or two? I have accidentally put mine in once at 180° out, and it would run, but had some oblivious timing issues.
08-16-2014, 04:03 PM
#40
Hey guys its been a while since I posted on here because I was trying everything on my truck. I just ran a compression test and all cylinders are good so now I know for sure its a sensor or even my ecu is bad. The problem has gotten worse now to where it won't hold an idle, it misfires like crazy, sometimes when I start it, it will die when I press the gas. And now its almost impossible to get it over 30mph. So now I'm checking my tps, cat and coil.
