engine knock after top end rebuild

[FR-425]

Sounds like very low throttle pre-detonation.

Double-tripple check your EGR vac lines. (proper routing)

A wide open EGR at idle will cause pinning at very low throttle.

In particular the DPFE:

The Lower/larger/longer hose on the rear port

The short smaller diameter on the front port.

And the EVR (EGR actuator)

...For other fuel related testing and pics, go here...
http://www.explorerforum.com/forums/showthread.php?t=221335

...This is for a 93-94 X...I can not find one for the 91-92 X yet..

Vacuum Diagrahm's

91-93 Explorer

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94 Explorer

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95-99 Explorer/Mountaineer 4.0L

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96-99 Explorer/Mountaineer 5.0L

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[jd4242]

Only thing is that his is a 94 and dont belive he has all that...but I do agree I think it low idle ping of some sort or hope so atleast...

 

[FR-425]

Yes, I know it's a 94', so's mine, that's why I'm chim'n in here.

I have an affinity for 94' owners.

And he does have the EGR system, you can see it in his video.

I hate to say it after all he's been through but I think he's gonna have to flash the PCM to get the EGR to cooperate with the higher compression heads. The exhaust manifold pressure differential is going to be different at least at idle. I'm hoping it will not be out of range of the DPFE to compensate.

Most likely though it'll just lope a bit at idle. Once he gets it sorted out.

 

[jd4242]

If he has egr shouldnt he have cps? Could have sworn I asked if he did..my 94 doesnt have either

 

[jd4242]

And where can you get a obd1 ecm flashed?? Only way I know to change a ecm is with a chip of some sort and your talking big money at that point

 

[FR-425]

And where can you get a obd1 ecm flashed?? Only way I know to change a ecm is with a chip of some sort and your talking big money at that point

Here:
http://v8tvshow.com/content/view/104/28/

Too much unless you're a serious mod madness guy? Yours is modded to the hilt I just assumed you cracked your eec-iv and tweaked it.

 

[FR-425]

If he has egr shouldnt he have cps? Could have sworn I asked if he did..my 94 doesnt have either

Mine does.

 

[jd4242]

Here:
http://v8tvshow.com/content/view/104/28/

Too much unless you're a serious mod madness guy? Yours is modded to the hilt I just assumed you cracked your eec-iv and tweaked it.

Im not tuned at all on my NA motor..my sc motor I am sct dyno tuned.I looked into having my sc motor flashed but couldnt find anywhere that could do it.I was told I would need a chip to tune it, why I went sct.if I could have my NA flashed cheap I would do it in a heart beat..

 

[jd4242]

Mine does.

Has cps? Like I was thinking earlier maybe his cps is a tooth off.

 

[FR-425]

Has cps? Like I was thinking earlier maybe his cps is a tooth off.

You talking Crank or Cam position?

I don't think he removed or did anything with those, did he?

other than the cam chain?

Well, he needs to double check all the usual suspect first then we can go nuts with the tune.

For right now he should pull the octane sorting plug to retard the timing 3* I would think.

 

[jd4242]

You talking Crank or Cam position?

I don't think he removed or did anything with those, did he?

other than the cam chain?

Well, he needs to double check all the usual suspect first then we can go nuts with the tune.

For right now he should pull the octane sorting plug to retard the timing 3* I would think.

Cam

Yea that would least tell if its a octane thing

 

[FR-425]

Cam

No need to move that to do the head, so hopefully he didn't.

His last post said he was headed to a shop, so we'll see if that gets us more info.

You know,,, He might have taken it out to get some more room, ,, and if he did he's got some PITA work to do to get it back timed right.

 

[FR-425]

And his gas is two months old!

 

[jd4242]

And his gas is two months old!

Think he said he was almost empty and has add some 93

 

[FR-425]

Think he said he was almost empty and has add some 93

Nice, can only get 91 out here.

 

[FR-425]

ardvark, isn't on line right now,

he's probably ripping hair out. Poor guy.. I'm check'n back later though this saga is get'n twitchy.

 

[jd4242]

Nice, can only get 91 out here.

when i let the motor site for awhile then start it back up, theres that same hollow bang from someplace. could it be the last or the 87 gas getting pushed out in front of the 93 or something?

 

[FR-425]

Hey, jd;

Did you go check out our TruckHaven run. Vids & pics are up!

 

[FR-425]

Updates?

 

[cerberusaardvark]

sorry, havent been able to post due to javascrpit problems. heres the update: everything is the same. i checked all the vac lines, and decided against messing with the throttle screw to set the idle since its going to the shop.

i dont think my car has a camshaft position sensor. i know it has a crankshaft position sensor though. im super positive that theres no way i could have messed up the timing, but im not ruling anything out.