Need a little help
nusch
01-15-2004, 05:28 PM
I have a 94 5.7L Blazer which won't time at all. When I hook the timing light up the light doesn't blink smoothly. It skips a few rotations and idles rough. If I hook the EST wire up it will die. Before I tried to time it, it had no power at all and I would have to accelerate very slowly or it would backfire and almost die. Here is everything I have replaced so far.
Fuel pump
Fuel filter
Distributor cap and rotar
Spark plugs
Spark plug wires
Ignition coil
Injectors
Fuel pressure regulator
EGR valve
PCV valve
Throttle body gasket
I replaced all of this except the throttle body gasket when I had a bad injector and just replaced the gasket today when my luck got worse. The only thing I can think of now might be the pick-up coil. Does anybody have any ideas?
Fuel pump
Fuel filter
Distributor cap and rotar
Spark plugs
Spark plug wires
Ignition coil
Injectors
Fuel pressure regulator
EGR valve
PCV valve
Throttle body gasket
I replaced all of this except the throttle body gasket when I had a bad injector and just replaced the gasket today when my luck got worse. The only thing I can think of now might be the pick-up coil. Does anybody have any ideas?
comp
01-16-2004, 06:50 PM
man your check book has got to be empty :eek7: not sure where ign.
gets it's signal on yours. i'll ask around hope somebody pipe's in before
your go broke....
gets it's signal on yours. i'll ask around hope somebody pipe's in before
your go broke....
brooster
01-16-2004, 07:14 PM
Start with some basics. Is it TBI? Have you brought #1 to TDC compression and aligned balancer with TDC on timing cover? Did you check and double check your firing order (18436572)? Have you checked for slack in timing chain (probably no more than 6-8 degrees)? Have you performed compression test or cranking vacuum test? Any noise in valve train when engine is running (possible bent push rods, bad cam lobe)? Any vacuum leaks (vacuum modulator, brake booster, etc)? If you decide you really want to check the pickup coil, ohm it out. I don't remember the spec, but I believe it's around 500-750 ohms. Also look for cracks around the center ring of the pickup coil. It's done got too complicated, time to start over with the basics.
Bronco2
01-16-2004, 07:40 PM
Agree with brooster and need to add 1 thing-have had a few of these trucks over the years that siezed and twisted the distributor shaft throwing the timing off.Acts very similar to a jumped timing chain.Just one more thing to check,throwing parts at the problem without a good diagnosis gets very expensive
nusch
01-17-2004, 08:01 PM
Most of the parts there that I have replaced was because of a bad injector but it seems everytime I fix something, something else decides to go wrong. the only thing I haven't checked vacuum wise is the brake booster and plan to check that and the pick up coil as soon as it stops raining. It is a TBI and I have checked my firing order many times.
nusch
01-17-2004, 11:14 PM
It started with a little hesitation in acceleration when I was above 45 mph and found two wires were corroded at the distributer. After fixing that it started to get worse gradually so I started trying to diagnose it and that is when I replaced all that to find out it was a faulty injector. It starts up perfect now and all I have replaced since was the base gasket at the throttle body to make sure it wasn't leaking but that is when it started to pour and that is the whole story up until now if that helps any.
72 rs
01-19-2004, 08:20 PM
have u checked the computer and or chip????
nusch
01-20-2004, 12:03 AM
I checked the pick-up coil and it came out to be 786 ohms but when I turned the distributer it would go up in the 900's and settle back. It says that it isn't supposed to do that and that it is supposed to stay constant. The computer has never even popped into my head that it would be the problem and I wouldn't know where to start with it.
michelq
01-20-2004, 07:51 AM
nusch.you need to check dist shaft magnet
nusch
01-20-2004, 03:27 PM
Does anyone have any ideas on how to get the roll pin out of the bottom of the distributor when a punch and hammer just doesn't make it budge?
72 rs
01-20-2004, 05:13 PM
never had one to stick like that.!. ru using the right size punch....just a thought. ru using a tabe vise to hold the distributer (sp)? so the pin has somewhere to go.
nusch
01-21-2004, 04:46 PM
I got it all worked out now and the pick-up coil was the problem. Now I have a different problem. It feels like my truck is stuck in one gear all of the time. It is sluggish when I take off and never tries for another gear. When I go faster in the 60's and 70's it needs to shift to a lower gear and stays reved up.
nusch
01-21-2004, 07:11 PM
I checked the fuel pressure and it was 12 psi. The timing is right on 0 degrees.
nusch
01-22-2004, 04:11 PM
I don't know what I did differently between yesterday and today but when I started it up this morning on my way out it ran perfectly. Just hope nothing else goes wrong for a while.
nusch
01-22-2004, 09:43 PM
I spoke to soon. My car now won't shift anymore and is stuck in the same gear it was before. When it was cold outside it ran perfect but once it started warming up it went straight back to not shifting.
comp
01-23-2004, 07:17 AM
:screwy: ????? recheck all connections, :eek7:
nusch
01-25-2004, 02:25 PM
I checked all the connections but it still does the same thing. It sounds like it is the transmission because the engine seems to run perfectly now. I readjusted the throttle valve cable and the park/neutral switch but it didn't help. I am going to change the filter and fluid out of the transmission because it has been a little over 2 years since that has been done. I hope that works. Does anyone know of anything else I can do?
Brandon2350
01-25-2004, 04:07 PM
I checked all the connections but it still does the same thing. It sounds like it is the transmission because the engine seems to run perfectly now. I readjusted the throttle valve cable and the park/neutral switch but it didn't help. I am going to change the filter and fluid out of the transmission because it has been a little over 2 years since that has been done. I hope that works. Does anyone know of anything else I can do?
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Buy a "For Sale" Sign...
old dawg
01-31-2004, 11:11 AM
I hope you've already fixed your shifting problem by now, but if not, you should check the trans electrical connector for corroded or loose pins, etc. This can certainly cause the intermittent shift problems you're having. You can disconnect it by squeezing the two pads on each side of the connector housing. :2cents:
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