1996 explorer swap problem, hesitation

[Mar1ne]

Are you running a canister purge solenoid?
Greg[/QU

No, I am not

 

[oldiron]

OK not really familiar with this setup yet, does it run an iac?
Greg

 

[73azbronco]

Cleaned injectors, but how do they spray? And honestly as long as they spray this should not be your WOT accel issue, that would be more idle issues.

If you are 100% sure fuel is not the issue, then next step is ignition, might try some junkyard pull offs to save dough. wires, ignition packs, change plugs and verify correct heat range and gap.

Or at this point it is driveable, I would take it to a ford dealer let them scan it and give you a part sheet to be replaced. Dealer software far more detailed than government OBD II generic info.

 

[onpier55]

Damn. I was hoping it was the o2’s reversed.

 

[Mar1ne]

Cleaned injectors, but how do they spray? And honestly as long as they spray this should not be your WOT accel issue, that would be more idle issues.

If you are 100% sure fuel is not the issue, then next step is ignition, might try some junkyard pull offs to save dough. wires, ignition packs, change plugs and verify correct heat range and gap.

Or at this point it is driveable, I would take it to a ford dealer let them scan it and give you a part sheet to be replaced. Dealer software far more detailed than government OBD II generic info.

I won't 100% rule out fuel, but I know my tank/pump/lines up to the rail are good. There shouldn't be a problem with the rail itself. Regulator is good. Injectors are clean. I connected them to a 9volt and ran brake cleaner through them and they all sprayed evenly, so I'm assuming thats ok. I still need to ensure pressure does not drop while driving. It's the last check Garry emailed me about.

I changed the cps, cam sync, and maf. I have not changed the tps or iac. I don't know if either of those could cause this. I looked up how to test them and it was like greek to me. I am going to do plugs, wires, and coil packs next. The plugs are new as well as the wires, but I won't count them out as the problem. It is drivable to get it to the local Ford dealer. I'll check in with them today to see if they can run a test for me.

 

[Mar1ne]

OK not really familiar with this setup yet, does it run an iac?
Greg

Yes. There is an IAC. I cleaned it and the spring/ plunger appeared to function properly.

 

[oldiron]

I believe 73AZ's recommendation may be your best option at this point. How close is the nearest dealership?
Greg

 

[Mar1ne]

I believe 73AZ's recommendation may be your best option at this point. How close is the nearest dealership?
Greg

Just a few miles down the road. I'll contact them tuesday when the service department opens and see what they can do.

 

[73azbronco]

Ford dealers pretty good to me. Had a ranger with bad idle I could not fix. $180 later, new AIC, works great.

 

[73azbronco]

I won't 100% rule out fuel, but I know my tank/pump/lines up to the rail are good. There shouldn't be a problem with the rail itself. Regulator is good. Injectors are clean. I connected them to a 9volt and ran brake cleaner through them and they all sprayed evenly, so I'm assuming thats ok. I still need to ensure pressure does not drop while driving. It's the last check Garry emailed me about.

I changed the cps, cam sync, and maf. I have not changed the tps or iac. I don't know if either of those could cause this. I looked up how to test them and it was like greek to me. I am going to do plugs, wires, and coil packs next. The plugs are new as well as the wires, but I won't count them out as the problem. It is drivable to get it to the local Ford dealer. I'll check in with them today to see if they can run a test for me.

IAC should not be an issue if it idles good, unless it sticks open causing a leak.

 

[oldiron]

Not at all saying that the iac is suspect in your case, but just this weekend I resolved a similar issue, The truck passed all tests with flying colors but still exhibited a slight miss at light throttle. IAC checked out fine both in koer test and multimeter tests and idled perfectly, replaced it on a hunch (educated guess) and issue was resolved. Now this was on an older obd1 5.0, and the obd2 are much more accurate. Worth a mention though.
Greg

 

[Mar1ne]

Local ford dealer said 1996 was too old for them to mess with.

I still need to check fuel pressure while driving. I'm waiting for a return call from a local shop. The owner/mechanic is an off road guy and I was told the best around at diagnosing problems. I want to see what he says before I start replacing more parts like plugs/wires etc.

 

[Mar1ne]

Is this the correct way to attach plug wires?

 

[904Bronco]

I used this...

 

[Mar1ne]

I used this...

Ok, good. Same configuration.

 

[onpier55]

Just changed My in tank fuel pump. Explorer pump. 90psi FYI
Have you gone to pick and pull and grabbed some spare coil packs to test?
I had a stall issue. Changed the iac and tps. Fixed my stall issue.

 

[Mar1ne]

Just changed My in tank fuel pump. Explorer pump. 90psi FYI
Have you gone to pick and pull and grabbed some spare coil packs to test?
I had a stall issue. Changed the iac and tps. Fixed my stall issue.

I changed out the TPS the other day, no change. I haven't gone to a pick and pull yet as we just don't have one very close. I do want to change out the coil packs though.

 

[DirtDonk]

Without going back over the discussion completely, does your new engine have a new cam too? Or is it the original Explorer camshaft still?
Just thinking outside the box in case your cam has the different firing order.

I'm guessing it would not though, since if the spark plug wires were not wired per the cam's order, it would run like crap all the time. Not so much with the injectors.
Your diagram about the firing order made me think about that.

Paul

 

[Mar1ne]

Without going back over the discussion completely, does your new engine have a new cam too? Or is it the original Explorer camshaft still?
Just thinking outside the box in case your cam has the different firing order.

I'm guessing it would not though, since if the spark plug wires were not wired per the cam's order, it would run like crap all the time. Not so much with the injectors.
Your diagram about the firing order made me think about that.

Paul

I explicitly stated to the machinist to keep the same cam in the motor. When I picked it up the two elderly gentleman told me they wanted to put a mustang cam in it against my wishes. I reiterated why I wanted the stock cam and they said they left it alone. As with a lot of machine shops I hear people have good experiences and some have bad experiences with them. I'm not sure what, if anything, assembly wise would cause these symptoms. Timing chain, valve adjustment? Count those problems out due to the runs well in the driveway but not driving symptom?

 

[DirtDonk]

I'm not sure what, if anything, assembly wise would cause these symptoms. Timing chain, valve adjustment? Count those problems out due to the runs well in the driveway but not driving symptom?

Timing chain? Not likely unless it was wayyyyy off.

Valve adjustment? Certainly, if it was too tight I guess, but if the stock heads and valvetrain are used, they're not adjustable. However, if they put new pushrods in and they were the wrong length, this might cause some trouble.

You can count most things out unfortunately, but a weak ignition spark or an improperly sized pushrod might do it.
Now you've got me thinking again so I'll have to re-read the thread to re-charge and re-calibrate my brain.

Paul