poorrichard
Member
- Joined
- June 15, 2014
- Messages
- 12
- Reaction score
- 0
- City, State
- Chandler, AZ
- Year, Model & Trim Level
- 1996 Explorer Sport 4x4
I recently purchased a '96 Ford Explorer Sport 4x4, w\233,000 miles on it.
Took it to emissions in order to register and title it, and it had 4 trouble codes,
P0401 insufficient EGR flow
P0402 EGR flow excessive at idle
P0340 camshaft position sensor circuit malfunction
P0420 catalytic converter efficiency below threshold
plus the MIL (Malfunction Indicator Light) would not turn on.
They gave me 2 months to complete the repairs and retest without paying another $27 to Arizona DOT.
Researched on the forum, and did the following:
Replaced DPFE sensor (mine was the older aluminum type, got a plastic one on eBay, $26) for the P0401/P0402 errors. Still got them after installing it, went on to the next codes.
Replaced camshaft position sensor and synchronizer, got an aftermarket CMP sensor and Motorcraft camshaft synchronizer (normally my quest for cheap parts would have led me to a $35 aftermarket synchronizer on eBay, but read too many problems with the cheaper aftermarket ones, so went with the Motorcraft one DA-2099 - $105 on eBay). Quite a job with some friends getting that done, the truck moved on us slightly while putting in the synchroniser, moved about 2-3 degrees past TDC on the crankshaft, tried to guestimate the slight forward motion of the synchroniser flag and seated it - and it started right up after completing the job, no P0340 code anymore.
BTW, the CMP sensor metal was completely missing on the old CMP sensor, and the camshaft synchronizer flag was twisted and bent badly on the old synchronizer.
Replaced both upstream 02 sensors (2 SMP brand for $26 on eBay) and ran a gallon of pure lacquer thinner (before the sensor replacement) per Scotty Kilmer, a youtube mechanic guru. The thinner didn't fix the P0420 code, but thought it was worth a try. Replacing the upstream O2 sensors DID fix it.
Replaced the check engine light in the instrument panel, by swapping it with the annoying ABS light that was on constantly. While I was at it, decided to swap the instrument panel backlights with some new LED lights. Found some great articles for this on explorerforum, chose blue 4-LED lights - looks AWESOME.
After all this was done, all the codes went away, except for P0401 and P0402 codes.
Looked for damaged hoses going up the to DPFE sensor, they appear OK.
Checked the EGR valve, it would kill the engine if we applied vacuum to it.
tested the amount of vacuum that was getting put to the EGR valve from the EVR / EGR solenoid, and it was very minimal, would only occasionally flicker off the zero vacuum line. A mechanic friend recommended replacing the EGR solenoid before doing a whole lot of electrical testing, might be a quick fix - did that, $30 at autozone, but still getting P0402, P0401 codes.
Drove it for about 25 miles after replacing the EGR solenoid, it only threw the P0402 code that night, but later next day, it showed both P0402 and P0401.
Not sure what to try next, is getting a bit exasperating.
If I don't get it fixed soon, (maybe too late already . .), I will have to pay ADOT another $27, but at this point, with $250 into the repairs already, I guess thats minor . . .
FYI, the engine seems to run good, to my untrained ear. During the camshaft synchroniser replacement, put in new sparks plugs and wires (HUGE wear gap on the old spark plugs). Idles at around 900 RPM.
Truly am in awe of the knowledge and experience on here. As a mechanic wannabe, this forum has given me the courage to tackle jobs I would normally have considered beyond my skill level. Thanks for any help you can give!!
Took it to emissions in order to register and title it, and it had 4 trouble codes,
P0401 insufficient EGR flow
P0402 EGR flow excessive at idle
P0340 camshaft position sensor circuit malfunction
P0420 catalytic converter efficiency below threshold
plus the MIL (Malfunction Indicator Light) would not turn on.
They gave me 2 months to complete the repairs and retest without paying another $27 to Arizona DOT.
Researched on the forum, and did the following:
Replaced DPFE sensor (mine was the older aluminum type, got a plastic one on eBay, $26) for the P0401/P0402 errors. Still got them after installing it, went on to the next codes.
Replaced camshaft position sensor and synchronizer, got an aftermarket CMP sensor and Motorcraft camshaft synchronizer (normally my quest for cheap parts would have led me to a $35 aftermarket synchronizer on eBay, but read too many problems with the cheaper aftermarket ones, so went with the Motorcraft one DA-2099 - $105 on eBay). Quite a job with some friends getting that done, the truck moved on us slightly while putting in the synchroniser, moved about 2-3 degrees past TDC on the crankshaft, tried to guestimate the slight forward motion of the synchroniser flag and seated it - and it started right up after completing the job, no P0340 code anymore.
BTW, the CMP sensor metal was completely missing on the old CMP sensor, and the camshaft synchronizer flag was twisted and bent badly on the old synchronizer.
Replaced both upstream 02 sensors (2 SMP brand for $26 on eBay) and ran a gallon of pure lacquer thinner (before the sensor replacement) per Scotty Kilmer, a youtube mechanic guru. The thinner didn't fix the P0420 code, but thought it was worth a try. Replacing the upstream O2 sensors DID fix it.
Replaced the check engine light in the instrument panel, by swapping it with the annoying ABS light that was on constantly. While I was at it, decided to swap the instrument panel backlights with some new LED lights. Found some great articles for this on explorerforum, chose blue 4-LED lights - looks AWESOME.
After all this was done, all the codes went away, except for P0401 and P0402 codes.
Looked for damaged hoses going up the to DPFE sensor, they appear OK.
Checked the EGR valve, it would kill the engine if we applied vacuum to it.
tested the amount of vacuum that was getting put to the EGR valve from the EVR / EGR solenoid, and it was very minimal, would only occasionally flicker off the zero vacuum line. A mechanic friend recommended replacing the EGR solenoid before doing a whole lot of electrical testing, might be a quick fix - did that, $30 at autozone, but still getting P0402, P0401 codes.
Drove it for about 25 miles after replacing the EGR solenoid, it only threw the P0402 code that night, but later next day, it showed both P0402 and P0401.
Not sure what to try next, is getting a bit exasperating.
If I don't get it fixed soon, (maybe too late already . .
), I will have to pay ADOT another $27, but at this point, with $250 into the repairs already, I guess thats minor . . .FYI, the engine seems to run good, to my untrained ear. During the camshaft synchroniser replacement, put in new sparks plugs and wires (HUGE wear gap on the old spark plugs). Idles at around 900 RPM.
Truly am in awe of the knowledge and experience on here. As a mechanic wannabe, this forum has given me the courage to tackle jobs I would normally have considered beyond my skill level. Thanks for any help you can give!!
