stoneone25
New Member
- Joined
- December 1, 2008
- Messages
- 6
- Reaction score
- 0
- City, State
- mabelvale Arkansas
- Year, Model & Trim Level
- 98 sport
I have a 98 ford explorer with 200,000 miles on it. It has the
4.0 sohc engine
When i start it in the morning since it has been getting cold
it rev to 2500 rpm when first started then will drop to around
500 then it goes up and down between 500 and 1000 rpm.it
sounds like it is not getting fire in all cylinder. runs rough.
sounds ok when reved up. After it warms up run good except
for a small miss when it cold outside.
Getting code
PO420
PO430
Po174
Po171
I have replaced spark plugs and wire
Maf sensor
Iac sensor
fuel filter
Don't know what to try next.
should I replace the O2 sensor. Don't know if that is the
problem since I'm getting code PO420 and PO430
Could it be the TPS?
4.0 sohc engine
When i start it in the morning since it has been getting cold
it rev to 2500 rpm when first started then will drop to around
500 then it goes up and down between 500 and 1000 rpm.it
sounds like it is not getting fire in all cylinder. runs rough.
sounds ok when reved up. After it warms up run good except
for a small miss when it cold outside.
Getting code
PO420
PO430
Po174
Po171
I have replaced spark plugs and wire
Maf sensor
Iac sensor
fuel filter
Don't know what to try next.
should I replace the O2 sensor. Don't know if that is the
problem since I'm getting code PO420 and PO430
Could it be the TPS?