Rangstang
Member
- Joined
- May 5, 2010
- Messages
- 194
- Reaction score
- 0
- Points
- 16
- Location
- Mesa, AZ
- Vehicle Year
- 2003
- Make / Model
- Ford
- Engine Size
- 3.0
- Transmission
- Manual
- My credo
- If it ain't broke, I can't fix it.
ADDED A COMPLETE UPDATE ON PAGE 2 SO NO ONE NEEDS TO READ EVERYTHING STEP BY STEP.
I've done 3 Ranger v8 swaps over the last 6 years prior to this one with no issues, but this one is proving challenging. Although, this is the first time I've used the long block from a Mustang instead of an Explorer. Specs when first fired listed below:
5.0L engine from 95 Mustang GT 5.0L - not rebuilt, only replaced all gaskets and seals
Upper/lower intake, throttle body, injectors (new o-rings), and fuel rail from 2000 Explorer
Exhaust manifolds are new castings from 65 Mustang with 289 V8
DPFE sensor from 2000 Explorer
PCM, PCM harness, and transmission harness from 2000 Explorer
MAF sensor from 2000 Explorer
IAC and TPS from 2000 Explorer
Coil packs from 2000 Explorer
O2 sensors from 1999 Explorer
NEW Autolite Platinum spark plugs gapped to .054" and BWD spark plug wires
No EGR on this due to the fact that I'm using the early exhaust manifolds, so there's no bung to run the EGR pipe. I've fooled the DPFE into thinking the EGR is present and the EGR remains in place, just with no vacuum line connected to the nipple and the bottom is plugged with a fitting.
Initially, I got a P0171 code, so I swapped out the O2s from the 99 set to the 2000 Explorer set I'm currently using. Cleared the code, drove it 12 miles. I then idled it for about 30 minutes another day. The next day, I pulled the plugs and found that cylinder 3 was ever so slightly tanned on the white insulating portion surrounding the electrode. All others were white like new. I bought a new plug and installed it in cylinder 3. I used a spark tester to verify that all cylinders are getting spark. Due to the fact that my primary wiring's connector on the LH coil pack that feeds cylinder 3 was cracked, I swapped it out with a spare that I had from another 5.0L Explorer motor.
I then removed the plenum and all injectors. I applied +12V to each injector individually and sprayed carb cleaner through them to verify that they were functioning and all of them had the 4 stream spray pattern. Replaced the injectors and checked resistance at the PCM connector through the harness to verify a complete circuit on all 8.
I then performed a dry, cold compression test on the engine and got 118 to 125PSI across all cylinders. Seems low, but I think it's because it's cold and dry. No one cylinder stood out. While doing that, cylinder 7's terminal came off at the plug. I bought a new set of Duraspark Gold wires and installed them yesterday.
I then read online that there have been a few cases of low alternator voltage causing misfires, but usually throwing a code for bad cam position sensor (which I didn't have). Just in case, I removed my alternator and had Autozone test it today and it put out +15.08V.
I'm at a loss at this point. I figured I'd buy a pair of coil packs just in case and see if that fixes it, but other than that, I can't imagine what it could be. Any help will be greatly appreciated!
I've done 3 Ranger v8 swaps over the last 6 years prior to this one with no issues, but this one is proving challenging. Although, this is the first time I've used the long block from a Mustang instead of an Explorer. Specs when first fired listed below:
5.0L engine from 95 Mustang GT 5.0L - not rebuilt, only replaced all gaskets and seals
Upper/lower intake, throttle body, injectors (new o-rings), and fuel rail from 2000 Explorer
Exhaust manifolds are new castings from 65 Mustang with 289 V8
DPFE sensor from 2000 Explorer
PCM, PCM harness, and transmission harness from 2000 Explorer
MAF sensor from 2000 Explorer
IAC and TPS from 2000 Explorer
Coil packs from 2000 Explorer
O2 sensors from 1999 Explorer
NEW Autolite Platinum spark plugs gapped to .054" and BWD spark plug wires
No EGR on this due to the fact that I'm using the early exhaust manifolds, so there's no bung to run the EGR pipe. I've fooled the DPFE into thinking the EGR is present and the EGR remains in place, just with no vacuum line connected to the nipple and the bottom is plugged with a fitting.
Initially, I got a P0171 code, so I swapped out the O2s from the 99 set to the 2000 Explorer set I'm currently using. Cleared the code, drove it 12 miles. I then idled it for about 30 minutes another day. The next day, I pulled the plugs and found that cylinder 3 was ever so slightly tanned on the white insulating portion surrounding the electrode. All others were white like new. I bought a new plug and installed it in cylinder 3. I used a spark tester to verify that all cylinders are getting spark. Due to the fact that my primary wiring's connector on the LH coil pack that feeds cylinder 3 was cracked, I swapped it out with a spare that I had from another 5.0L Explorer motor.
I then removed the plenum and all injectors. I applied +12V to each injector individually and sprayed carb cleaner through them to verify that they were functioning and all of them had the 4 stream spray pattern. Replaced the injectors and checked resistance at the PCM connector through the harness to verify a complete circuit on all 8.
I then performed a dry, cold compression test on the engine and got 118 to 125PSI across all cylinders. Seems low, but I think it's because it's cold and dry. No one cylinder stood out. While doing that, cylinder 7's terminal came off at the plug. I bought a new set of Duraspark Gold wires and installed them yesterday.
I then read online that there have been a few cases of low alternator voltage causing misfires, but usually throwing a code for bad cam position sensor (which I didn't have). Just in case, I removed my alternator and had Autozone test it today and it put out +15.08V.
I'm at a loss at this point. I figured I'd buy a pair of coil packs just in case and see if that fixes it, but other than that, I can't imagine what it could be. Any help will be greatly appreciated!
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