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1996 explorer swap problem, hesitation

sanndmann3

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Jun 13, 2007
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Any chance its a bad fuel regulator? If it was dumping fuel back to the tank would result in low fuel pressure... just a thought.
 

73azbronco

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Injectors are not that bad a thing to pull, but be careful with pressurized systems, depressurize the rail first/
 
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Mar1ne

Mar1ne

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Sierra Foothills, CA
clean the injectors or at least spray test them.

From a manual on EFI:

A vehicle that hesitates while accelerating or while driving up a hill may have a weak fuel pump. ... Dirty fuel injectors may cause the engine to run lean which will in turn, cause hesitation when accelerating.

I’m going to get a stainless tank with pump from WH this week. If it’s the pump this will figure it out.
 

oldiron

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I quickly re-read your initial post and I don't see anything mentioned about timing, specifically initial timing. Any idea what it is?
Greg
 

73azbronco

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I would not buy a tank until you know anything about the injectors, you may be paying $1000 to find out you still need injectors, check the injectors man!!
 

Timmy390

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I recently had a plug start acting up. Random misfire and popping out the exhaust. The issue would come and go. Cold motor was when it was most noticeable.

Tracked the cylinder down via thermal gun. Thought it was everything BUT the plug you know cause it couldn't be that. Well it was a plug. Never have seen anything like that before.

Just a thought....


One other thing....you running a cat? Plugged or failing cats can cause all kinds of issues under load.....

Tim
 
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Mar1ne

Mar1ne

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I recently had a plug start acting up. Random misfire and popping out the exhaust. The issue would come and go. Cold motor was when it was most noticeable.

Tracked the cylinder down via thermal gun. Thought it was everything BUT the plug you know cause it couldn't be that. Well it was a plug. Never have seen anything like that before.

Just a thought....


One other thing....you running a cat? Plugged or failing cats can cause all kinds of issues under load.....

Tim

No cat. Plugs look good, but so does everything else so I won’t count them out.
 
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Mar1ne

Mar1ne

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I quickly re-read your initial post and I don't see anything mentioned about timing, specifically initial timing. Any idea what it is?
Greg

Timing is edis driven and as far as I know it’s plug and play. Cam sync was stabbed with the otc tool on tdc compression stroke. I don’t think there’s anywhere else to go from there.
 

oldiron

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Timing is edis driven and as far as I know it’s plug and play. Cam sync was stabbed with the otc tool on tdc compression stroke. I don’t think there’s anywhere else to go from there.

I believe you're correct on the edis system.
 

hankjr

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are your plug wires new? when i was putting my new ones on, i REALLY had to be sure they clicked on. i noticed on the third or fourth plug that something didnt fell quite right and half the ones i had already done took more force to feel the engagement.

Hank
 

onpier55

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Oct 19, 2017
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Roseville Ca
Just going to throw this out. Try switching wires from left to right on o2 sensers. I had mine reversed. Idled great. Ran like crap like at 2500 rpm. Loaded up and popped a lot. I just replaced my in tank fuel pump and it runs at 90 psi at rail.
Good luck.
 

904Bronco

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Just going to throw this out. Try switching wires from left to right on o2 sensers. I had mine reversed. Idled great. Ran like crap like at 2500 rpm. Loaded up and popped a lot. I just replaced my in tank fuel pump and it runs at 90 psi at rail.
Good luck.

I had forgotten about that Hick-up you had... No Cost to try that one...
 
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Mar1ne

Mar1ne

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are your plug wires new? when i was putting my new ones on, i REALLY had to be sure they clicked on. i noticed on the third or fourth plug that something didnt fell quite right and half the ones i had already done took more force to feel the engagement.

Hank

They are new, but they're from Amazon and are probably not true Motorcrafts after inspecting them a bit closer and reading on here that they are often knocked off. They are a pain to press down and seat properly for sure.
 
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Mar1ne

Mar1ne

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Mar 25, 2016
Messages
158
Loc.
Sierra Foothills, CA
Just going to throw this out. Try switching wires from left to right on o2 sensers. I had mine reversed. Idled great. Ran like crap like at 2500 rpm. Loaded up and popped a lot. I just replaced my in tank fuel pump and it runs at 90 psi at rail.
Good luck.

I'll try this. Thank you for the suggestion.
 
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Mar1ne

Mar1ne

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Mar 25, 2016
Messages
158
Loc.
Sierra Foothills, CA
Rebuilt/ cleaned the injectors. No change.

Put the WH stainless fuel tank with in tank pump. No change.

Switched the O2 sensors around. No change.

I need to double check the fuel pressure while driving. The shop I had troubleshoot it supposedly did and said it was good at WOT. I will check myself. Following that, if it is indeed good, I will no longer think fuel is the problem.

All plugs are reading the same tan color. Whatever the problem is it seems to be affecting all cylinders equally. Inadequate spark? Electrical interruption?
 
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