2.9 engine miss?

[Spitfire1975]

That's what I thought so I put the old computer back in. What is in the distributor that advances the timing? I changed out the pickups and didn't really notice anything else in there. Almost wondering if it is related to my timing chain and I am not really at 10*.

 

[Bronco_Chuck]

im not sure how it advances the timing but i think it would have to be something mechanical not sure tho. i dont think ive had any of my bII's exactly at 10* since i dont have a timing light. if the timing chain was off that would be a whole mess of problems. since the valves would be opening and closing at the wrong time. basicly you have 120* of crankshaft rotation from where the intake valve closes till ignition. not sure how you would check that but that would be a good estimate.

 

[Spitfire1975]

I think I will recheck the temp sensor, recheck/replace the TPS and MAP and see what I can do about checking the cats. Sounds like a plan......

 

[Bronco_Chuck]

cool. sounds like a plan.

 

[Spitfire1975]

I'll let you know what I find.

 

[adsm08]

That's what I thought so I put the old computer back in. What is in the distributor that advances the timing? I changed out the pickups and didn't really notice anything else in there. Almost wondering if it is related to my timing chain and I am not really at 10*.

The pickup is what gives a timing advance signal. That's the only thing in there.
The timing is the cam timing, not the spark timing (yes, I know its a cam driven distributor and thus they are related) but the 10* mark on the pulley is indicating degrees of crankshaft rotation, it will always give you an accurate reading on where your spark is going. The timing chain won't effect that.

 

[Spitfire1975]

Good. Then the issue should not be coming from the chain or the distributor.

 

[Spitfire1975]

I changed the pickup because I was getting intermittent spark on the #1 cylinder. Seems to have resolved that issue.

 

[Spitfire1975]

So I had changed the pickup because of the intermittent spark on #1, right. Checked the the wires again today, and was now getting intermittent spark on #'s 4 and 6. Crap. Changed the pickup for a brand new one. Still getting intermittent spark on 4 and 6 though not as bad on 4. Now, mind you, I am using my inductive timing gun to check for spark. This does work, does it not? Truck is still missing/ sputtering. TPS is topwire = .20, middle wire = .99 bottom wire = 5.25. If I unplug the one on the engine the engine doesn't really change any. Idle lowers if I put it on my spare not hooked to the throttle. Hook it back up to the one on the throttle and the sputtering gets worse. Hook it back up to the spare, nothing changes. Is it safe to say I need to just buy a new TPS? My wife is getting pissed I keep spending money on this thing and not getting anywhere. Temp sender tests ok.

 

[Spitfire1975]

And maybe you should try and get your site working right instead of telling people who deserves respect......

 

[Bronco_Chuck]

not to sure what this banning talk is about. but when you say your getting intermittent spark you mean it sparks every other time it should?

 

[Spitfire1975]

it is real random. It will spark consistently for a few seconds then no spark for a second then consistent for a second then no spark for a few seconds. No pattern to it. If I unplug the wire completely the engine runs horribly (like it is completely missing a cylinder, which it is)

 

[Bronco_Chuck]

could it be a bad cap or rotor? because you said that the same thing was happening to the No 1 wire before. and 1,4,6 are all right next to each other.

 

[fordman4x492]

my truck has the same problem bit you cant hardly tell its miss fireing by listening to it. when it starts to miss the whole trick starts to shake a little bit.

 

[Spitfire1975]

Brand new cap and rotor, plus it looks good. Can't see any streaking or cracks or anything out of the ordinary. I will say this. I was just out unhooking the ground to try and reset the computer and the negative cable was WAY to loose. I just pulled it right off the post with no effort. I would imagine a BAD GROUND could do this? I am gonna be pissed if that is all it was......will know soon