I am going to start this over with a different approach.

First, this is not going to be one of those problems that can be solved with a code reader. In fact, if the truth were known the idea that a code reader is going to solve this problem has contributed to me spending a lot of money chasing symptoms instead of getting to the heart of the problem. Oxygen Sensors, Engine Coolant Modules are not going to solve this problem.

We have spark, the timing is right, it has a new timing chain set on it, new injectors, plugs and just about every electronic sending unit has been replaced. Anything that has come up on the code reader has been replaced including those from the last go 'round.

So, Saturday when I got off of work I went by and installed the new ECM on it as 12 came up on the code reader. No change. I checked for spark, plenty of spark so I sprayed a liberal amount of Either in the intake throat...enough that it should have done something even if it were to fly apart. Nothing! The only time I have EVER had anything close to this is when a driver turned up a Cummins and caused it to put a hole in all six pistons! No compression. This pickup is acting like it has some valves stuck open. We put a compression tester on #1 and #4 and it is at about 90 lbs.

When I have the time, I am going to test every hole for compression. I think this is a mechanical problem, it acts like the timing chain has jumped time but I have installed a new timing set (and yes I did it right).
This pickup had been running very rich and using a lot of gas. I know I need to do a complete rebuild on it eventually but for now I just need it start.

Any ideas? Any similar experiences?

 

What codes are you getting? Just because you get an oxygen sensor code doesn't mean it is bad. You may not be drawing the right conclusion from the codes.

 

Just put that 16v71 in there.

 

Are you sure the dizzy is in the right place?

 

If you have spark and fuel, then either compression or timing. You say plenty of spark, what color is the spark? You're right, it should have did something with all that either in there, even if it was to backfire.

 

The spark could he healthier, but it is there. The timing is set, new chain and sprockets, new coil, ignition module, new plugs and wires. The code was 21 and it indicated a ECM was out of specs so I changed it.....Yes, those code readers might be the best part salesmen there are.

So, I am thinking mechanical. I would not be surprised if we didn't have a bunch of valves stuck open. I did a compression test on 1 and 5, 90 PSI. So when I get time I am going to do them all. Funny, the pickup is about 12 miles away. It was either that or get it towed.

Aktech....I can't hear you, your radio is breaking up.

 

Oh yes. It isn't gonna be an obvious fix, but I am going to get to the bottom of it. I have a friend down in Cleburn Texas that will provide the explosives if I don't.

You are all invited to attend the great FoMoCo send off if it happens.

 

Pull your valve covers off if you fear internal issues.

 

A vacuum leak will cause O2 sensor codes.

 

Valve covers, heads. Yes I would have liked to have avoided a tear down, but I actually believe this is what it is going to take to find it so I may as well get ready for a complete engine rebuild. I have no problem doing it, but I should have done as soon as I got the pickup. This is what I get for trying to breathe new life into an old engine that has just severely abused.

I'll bet on the cam being shot. As far as the vacuum problems? When I go back in, I am going to rid myself of that plastic junction at the back of the engine and just go point to point. But if the cam is shot there isn't going to be much vacuum to be had anyway and it would explain a lot.