Old, New guy, with Old Problems

[Ripsaw]

Hello all, First post here, regrettably so. This is a last ditch desperation move to join a forum and come here for help....Why ? Because of my pride as a man. I am 58 years old, and was raised to handle all problems myself, and never ask for anything from anyone. So you can see this is tough for a guy like me. But I must swallow my pride and ask for help.

I have a 1991 C1500 Silverado Pick-up truck. I have searched high and low on the net for the fix on my problem. The truck has 211,000 miles and has been very well taken care of. Oil changed every 3,000 miles for life, all highway miles. All filters too. Never had a problem till the fuel pump quite. I replaced it and the filter on the end.....on the road again !

Rocked on for several thousand miles after that with no troubles....then one day it died at a redlight, cranked right back, but I noticed is was idling lower than normal and was cycling between 600-800 RPM's on the tacometer, I noticed the idle would start surging up and down, then eventually, it would not idle and die, if I didn't keep gassing it.

Now for some history.....my pride.... I grew up with a Dad that raced with A.J. Foyt back in the day on the roundy rounders...dirt trackin it....we did all our own builds and work. So I am by no means clueless.....enter my pride and past life experiences for problem solving. But I am a carb guy, and knew nothing about TBI's....or computer crap either. So I did some searching and bought and replaced the idle air control valve, got it up to 45 MPH to reset it as per instructions. Then I replaced the PCV valve and the Coolant temperature sensor, oxygen sensor, and checked all the wires for grounding out somewhere, and for vacuum leaks anywhere. Found a couple of slight leaks in vacuum hoses and repaired those too. All new plug wires and plugs, cap and rotor.

I found a wiring diagram for the injectors in the TB, and have learned the red and white leads, one from each injector, goes to the EGR Solenoid, whatever in the heck that is,...or does....Help for that? And, I found the green and blue go to ground. I learned how to check the power to each from the EGR with a light, and have heard that if any wire is grounded out, it will cause the injectors to flood and pour fuel. That is what is happening, they are pouring, not spraying, and it is continual and will not crank or run now. I bought a rebuild kit, checked injectors, they are good, and rebuilt the entire TB.

I also installed new timing chain and gears because at first, it all acted like a timing problem, back firing and all sorts of crazy stuff. Then I got back to searching for answers. I came across a post on a forum where a guy had the same problem as me. ( Actually hundreds and hundreds of guys are having the same problem, with no solutions after changing everything).... He replaced everything, still no joy. Finally, he had a mechanic buddy tell him that there is a pick-up coil in the distributor, just under the rotor and below the vacuum advance assembly. If that coil goes bad, as his did at 177,000 miles, it will flood the injectors. He also said that the module and the pick-up coil on the distributor, in unison with the MAP sensor and throttle positioning sensor, is what tells the injectors to pulse, and how much....if it's bad , they flood.

Now the weird part. After installing the timing chain and gears, and getting ready to bust it off after building the TB, I got the timing mark to spec called for on the harmonic balancer, checked number one for TDC with plug pulled and long screwdriver and moved it back and forth to make sure it was topped out, then pulled the distributor cap. The rotor was facing 180 degrees out from number one ! Keep in mind, I never pulled the distributor to install timing components, and only a complete idiot could screw that up when attaching new gears. The crank has a keyway, and the cam has a nipple and three bolts. The timing gears have a dimple for 6 and 12 O'clock....it can only work one way. Mine was right. So I am completly bumfuzzled now.

So I think about it awhile, and decide to try it anyway. My wife got in, turned the key, and it still kept flooding. I turned the distributor back and forth, and had it running for a moment, albeit badly because of the flooding. Then it died and backfired a little, just fuel, no fire out the TBI. So I sent her back inside to scratch my head awhile. Then I decide, the gear on the bottom of the distributor must be bad, for the rotor to be out 180. But the slot for the oil pump won't allow that without a broken shaft on the distributor.... Right ?
So before pulling it, I decided to move all the wires to the firing order to match up with the right cylinder...no joy, wouldn't crank, big surprise.

So I quit for the day. Go back out the next day, move wires where they go, went through the whole timing procedure again...done it a thousand times in my life. Pop the cap to check the rotor...and holy moley...it is back on number one with timing mark lined up and cylinder up. What the heck ???? So now I know it has to be the gear at the bottom of the shaft is screwy. I pull the distributor....nope....it is fine, no sheared pin, no gear damage from cam being bad either. So I am totally freaked out now....so freaked out in fact, that I forget to stick a screwdriver in the oil slot and try to turn the rotor to see if shaft is broken like in a stair step across, so it could be jumping up and over, then back again. Then I realize that if that was the case, the rotor would have raised up and damaged the contact points in the cap, no damage there either BTW. I restabbed the distributor....no joy, no cranking....one freakin problem at a time I decide. I have to stop the injectors from flooding. But how did the rotor get 180 off and correct itself ? Have I gone senile I think to myself. What am I missing guys ? I use to be a good mechanic,..what happened ?

I did not want to keep throwing money at this until I find it, I am a 100% disabled vet and really don't have it to throw, it is not service connected, so I have a minimum pension of $378 a month. Next is the MAP sensor and TPS, The EGR Solenoid, then maybe a distributor....depending on what you guys think ? That's another 200 bucks ! I hear something called the ECU is involved also....couldn't tell you where it is or what it does, or even what the letters stand for, but I do know it is expensive. BTW, new injectors, in case my test were wrong, are $135 each....another 270 bucks, and the only thing not new in the TB.

Sure could use some help ? Ideas, reflections, suggestions or tips....welcome in this thread....... Best regards.....Rip.