1998 f150 4.6 rough running, Ideas welcomed
05-18-2010, 04:11 PM
#1
Ford Tough !!
Thread Starter
1998 f150 4.6 rough running, Ideas welcomed
This is a 98 f150 I just bought with only 124,000 miles on it, prior to buying had the CEL checked & indicated needed oxygen senors on the # 1 bank. This explained why would be rough running, so for the price I bought it & hoped to have it on the road in no time.
1. Instead of just buying the 2 o/2 sensors I bought all 4 just to be safe.
Made no dif, check engine light came back on after resetting,
2. so scanned again, this reading said the TP sensor & Air bypass valve, bought & installed both, had the CEL reset, went for a test drive, a lil bit better, not much then CEL came back on.
3. Another scan, results - EGR valve & running lean on bank 1, bought new EGR valve, new spark plugs, MAF cleaner & 2 bottles of Lucas fuel cleaner.
4. I installed the EGR valve, changed the plugs, (looked like original ones in it), pulled out the MAF sensor & cleaned it up good, (was not bad looking at all), I also tested it by the book for volts, checked out ok. In addition, I went ahead & checked the primary & secondary of both coil packs, (both packs dead on with the Haynes book), I also ohmed my plug wires, all 8 good. Also while working on it, flushed out the radiator good & installed new anti-freeze just to help clean it out.
When I clear the CEL each time I have done it both ways, by disconnecting the negitive battery cable for 5 plus minutes and or cleard the light with the scanner, then test drive the truck for 5 to 20 miles at a time.
Still running rough and a few added puzzling notes.
I can clear the light & drive for 6 to 8 miles before light comes back on, rescan and codes be something I already changed out. Clear the light again, drive, rescan and be something totally different without doing anything, clear out, drive, light returns, scan and again be a different code.
Now while test driving if I get on it, (not up to 70 or 90 mph, just a quick get up to speed 45 to 55 tops), I will loose all oil pressure, needle drops to nothing & the engine oil light will come on as well. I stop, shut the key off & start it back right away & the pressure returns to normal & holds fine with normal driving. Once just to see if false reading or not once needle dropped & oil light came on I drove it about 2 plus miles back to the house & I did not hear knocking or tapping even. So false reading maybe?
But just strange it only happens if I step on it a bit more than one would do normally.
If no suggestions, I guess it is time to find a shop... Keeping my fingers crossed here til I hear something.. lol
puzzled in SC & thanks in advance!
1. Instead of just buying the 2 o/2 sensors I bought all 4 just to be safe.
Made no dif, check engine light came back on after resetting,
2. so scanned again, this reading said the TP sensor & Air bypass valve, bought & installed both, had the CEL reset, went for a test drive, a lil bit better, not much then CEL came back on.
3. Another scan, results - EGR valve & running lean on bank 1, bought new EGR valve, new spark plugs, MAF cleaner & 2 bottles of Lucas fuel cleaner.
4. I installed the EGR valve, changed the plugs, (looked like original ones in it), pulled out the MAF sensor & cleaned it up good, (was not bad looking at all), I also tested it by the book for volts, checked out ok. In addition, I went ahead & checked the primary & secondary of both coil packs, (both packs dead on with the Haynes book), I also ohmed my plug wires, all 8 good. Also while working on it, flushed out the radiator good & installed new anti-freeze just to help clean it out.
When I clear the CEL each time I have done it both ways, by disconnecting the negitive battery cable for 5 plus minutes and or cleard the light with the scanner, then test drive the truck for 5 to 20 miles at a time.
Still running rough and a few added puzzling notes.
I can clear the light & drive for 6 to 8 miles before light comes back on, rescan and codes be something I already changed out. Clear the light again, drive, rescan and be something totally different without doing anything, clear out, drive, light returns, scan and again be a different code.
Now while test driving if I get on it, (not up to 70 or 90 mph, just a quick get up to speed 45 to 55 tops), I will loose all oil pressure, needle drops to nothing & the engine oil light will come on as well. I stop, shut the key off & start it back right away & the pressure returns to normal & holds fine with normal driving. Once just to see if false reading or not once needle dropped & oil light came on I drove it about 2 plus miles back to the house & I did not hear knocking or tapping even. So false reading maybe?
But just strange it only happens if I step on it a bit more than one would do normally.
If no suggestions, I guess it is time to find a shop... Keeping my fingers crossed here til I hear something.. lol
puzzled in SC & thanks in advance!
