Valve job, rebuild or replace engine 140k

[thunder92]

I'm not familiar with using dye for testing fuel injectors but it sounds like a way to check for leaks instead of no flow.

ya, never heard of it either. The way he explained it was to make sure the injector was firing fully and correct pattern etc.... I still don't get it.

Anyway, I just listened to the injector again and it sounds about the same as the others. Not able to meter it unfortunately because its under the dang manifold.

I did get the pcv valve off and holy smokes was that thing oily! I cleaned her good and put it all back together. Test drive feels good so far but I suspect the new plugs of that. Usually takes a while to foul the plug. I have a anti fouler sleave on there too since it usually seizes against the block and is impossible to break. Thanks for the help guys!!!

 

[Number4]

Might have been referring to this.

http://m.harborfreight.com/11-piece...t-97959.html?utm_referrer=direct/not provided

 

[thunder92]

I just re-read the invoice. They called it a Rel. injector flow test. I don't think they would have taken the manifold off to noid test the injectors. Too time invasive.

update: found it!
pretty cool.

And the pwr bal test was prob something like this:

These techs probably didn't even have to get their hand partially dirty!

This truck did have some overheating issues at one time. Think I'll change out the coolant temp sensor while i'm in there. Cheap insurance.

 

[2000StreetRod]

clever injector test

That relative injector flow test is very clever and a fairly accurate method. The 4th generation has a fuel pressure sensor on the fuel rail.

I installed one on my fuel rail when I added my M90 supercharger and my high flow fuel pump.

I ended up moving it from the driver side to the passenger side for wire loom clearance.

It's wired to a PWM fuel pump controller.

So I'm going to assume that all injectors are pulsing and flowing correctly. I'll have to spend some time coming up with an alternative explanation for your spark plug rapid erosion.

 

[thunder92]

wow, nice work streetrod. That is impressive!

 

[2000StreetRod]

found it on internet

I can't take the credit for the PWM fuel pump controller. It was available as a kit or assembled online. I just happened to find it while searching for data on the fuel pressure sensor. Many years ago I would have purchased the kit and assembled it myself since I have a degree in electrical engineering. However, at the age of 68 my eyes are no longer good enough for detailed soldering so I bought it assembled and tested. It was designed for motorcycle and compact vehicle fuel pumps but with added heat sinks has been able to handle my Aeromotive Stealth 340 lph fuel pump.

 

[thunder92]

Well 130 miles and the check engine finally came back on. Misfire is back! Figured.
Im looking for a bridge to jump off

 

[2000StreetRod]

cylinder 5?

Is it still cylinder 5 or now another cylinder? Frankly, I'm about out of ideas for a solution.

 

[thunder92]

Yes, cylinder 5 misfire again. I really wonder if I can trust the results ford found.

Anyone with any ideas let me know. Thanks

 

[coco944x4s]

Vacuum leak at the intake manifold. Could be leaking right at the head and leaning the one cylinder out. You haven't mentioned any lean codes, so that rules out major manifold leak. Cracked intake runner maybe? Either pull the intake and inspect, or try the spray test with darn cleaner. Have you replaced the coil? Just because it "looks" good doesn't mean that cylinder pressures aren't too much for it to over come and the plug is fouling. Try switching the coil ends of #5 plug wire and the one right beside it. Coil fires both posts at once, switching the two would move the miss if it is the coil.

 

[thunder92]

thanks for the reply. Yes, I changed the coil a while back. Actually brand new coil pack. I will check for a manifold leak again though. I should have a vacuum tester in the mail today too. I have new gaskets I had ordered anyway. Maybe I'll get lucky and that will be it. The other clue to this possibly is it starting happening shortly after I had a rebuilt transmission put in. Maybe something to do with that? Vacuum hoses etc.... not put back correctly?

Thanks for the help.

 

[coco944x4s]

The shop that did the transmission might have inadvertently caused the intake to crack or stressed it and separated the intake from the head. I'd buy a can of carb cleaner and spray around it some. It will run better if you found the leak.

 

[thunder92]

Nothing

Sprayed carb cleaner and then propane all around and nothing. No leaks from what I can see

 

[thunder92]

idea

I'm wondering if one of these things I did fixed the issue but the anti fouler sleeve on the spark plug set off the code? I've been scared to take it off because its near impossible to get off when it fouls out. I may just have to take the risk and take it off. The plug was not even fouled out this time. Looked fine. Maybe the computer just didn't like the way it was firing with the sleeve on it.

 

[thunder92]

13.5 hg vacuum

Ok, finally did the vacuum test. Its low. 13.5 hg at idle. Go's up a little with reving and then go's back down after 2-3 seconds when i let it idle again.

I don't know exactly how to read it but I know its low. Don't know how ford missed this one. Anyone?

 

[2000StreetRod]

smoke test

In my opinion the only reliable way to locate a vacuum leak is with a smoke test unless the IAC valve electrical connector is disconnected and the throttle plate is opened enough that the engine will still idle. Even then there are a lot of potential spots that are inaccessible when spraying some aerosol at the engine.

I agree that your vacuum is weak. As I recall mine was around 25 in-Hg before I installed the supercharger. Now its only about 17 and I plan to build a smoke generator but haven't gotten to it yet.

Normally vacuum will get weaker when the engine is accelerating and stronger when you release the accelerator. Mine still exceeds 20 in-Hg when I let off the accelerator and then returns to 17 at idle.

Is the vacuum steady at idle or does it jump around?

 

[thunder92]

Its steady at idle.no jumping. More concermed with something internal
Wrong or timing chain etc.... ive tried forever to find a leak and cant.

 

[jsmn4vu]

If the vacuum is low AND the compression is good (check that before proceeding), then there must be a leak somewhere -- anywhere -- between the throttle butterfly and the attachment of the intake manifold to the heads.

 

[thunder92]

Well, I decided to just change the manifold gaskets since i had them already. No change. Still low vacuum. Good thing is this time the engine light came on the plug still looked fine and was not seized or hard to get out. Gonna test the egr tonight. And take of the manifold and check rocker arms.

I'm thinking my vaccuum is fine now. I've heard that you deduct 1hg for every 1000ft above sea level. That would mean -5 for me.