Engine misses 3500 ROM
shawn1963
09-01-2007, 09:25 AM
I have a 2002 with 220,000 km. When you 1st drive the car cold you can accecerate the car right up 4800 - 5000 RPM in 2nd & drive, with no engine miss. Soon as the engine gets warm (5 to 8 minites) the engine will miss at 3300 - 3500 RPM. This is only in 2 & drive, 1st is fine, and I've never driven the car fast enought to see if it does the same in overdrive. I have installed new platum plugs, cap, rotar, fuel filter, and plugwires, no change, any ideas whats wrong?
taillight
09-01-2007, 10:09 AM
Pull any trouble codes ?
shawn1963
09-02-2007, 09:06 AM
Yes 1131
shorod
09-02-2007, 10:50 AM
Welcome to the forum!
Code P1131 would indicate that there is a lack of switching for heated oxygen sensor bank 1, sensor 1, fuel trim is at the limit. According to the factory service manual, this can be caused by the following:
Electrical:
Short to VPWR in harness or HO2S
Water in harness connector
Open/Shorted HO2S circuit
Corrosion or poor mating terminals and wiring
Damaged HO2S
Damaged PCM
Fuel System:
Excessive fuel pressure
Leaking/contaminated fuel injectors
Leaking fuel pressure regulator
Low fuel pressure or running out of fuel
Vapor recovery system
Induction System:
Air leaks after the MAF
Vacuum Leaks
PCV system
Improperly seated engine oil dipstick
EGR System:
Leaking gasket
Stuck EGR valve
Leaking diaphragm or EVR
Base Engine:
Oil overfill
Cam timing
Cylinder compression
Exhaust leaks before or near the HO2S(s) Looks like you have a few items to check. If a quick check of most of these items does not reveal anything, and you are comfortable doing it, I'd suggest you get a can of SeaFoam and use it to perform a cylinder de-carbonization. Instructions are on the SeaFoam can. Maybe as the engine warms up, the carbon is becoming a sponge and absorbing the fuel. Also, if you have a fuel pressure tester (or don't mind spending $25 or less to buy one), make sure your fuel pressure isn't dropping when warm. It wouldn't be a stretch to suspect that your fuel pump may be getting weak.
-Rod
Code P1131 would indicate that there is a lack of switching for heated oxygen sensor bank 1, sensor 1, fuel trim is at the limit. According to the factory service manual, this can be caused by the following:
Electrical:
Short to VPWR in harness or HO2S
Water in harness connector
Open/Shorted HO2S circuit
Corrosion or poor mating terminals and wiring
Damaged HO2S
Damaged PCM
Fuel System:
Excessive fuel pressure
Leaking/contaminated fuel injectors
Leaking fuel pressure regulator
Low fuel pressure or running out of fuel
Vapor recovery system
Induction System:
Air leaks after the MAF
Vacuum Leaks
PCV system
Improperly seated engine oil dipstick
EGR System:
Leaking gasket
Stuck EGR valve
Leaking diaphragm or EVR
Base Engine:
Oil overfill
Cam timing
Cylinder compression
Exhaust leaks before or near the HO2S(s) Looks like you have a few items to check. If a quick check of most of these items does not reveal anything, and you are comfortable doing it, I'd suggest you get a can of SeaFoam and use it to perform a cylinder de-carbonization. Instructions are on the SeaFoam can. Maybe as the engine warms up, the carbon is becoming a sponge and absorbing the fuel. Also, if you have a fuel pressure tester (or don't mind spending $25 or less to buy one), make sure your fuel pressure isn't dropping when warm. It wouldn't be a stretch to suspect that your fuel pump may be getting weak.
-Rod
shawn1963
09-04-2007, 07:46 PM
Thanks Rod, any ideas on where I should start 1st?
shorod
09-04-2007, 10:51 PM
Yep, see the last paragraph of post #4. ;)
-Rod
-Rod
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