Engine Performance problem
2003 Kia Spectra 4 cyl Front Wheel Drive Manual 54000 miles
I have a 2003 kia spectra with misfires on cylinder 1, 2 and 3. DTC codes P0300, P0301, P0302, P0303. I have replaced plugs (properly gapped), wires, coil packs, fuel filter, fuel injectors. No effect.
Noid light shows pulse signal at fuel injectors. Compression check shows 140 on cyl #1, 150 on cyl #2-4
What is the fuel pressure reading? And, can you describe how it's driving going down the road? Please advise.
April, 15, 2009 AT 5:25 PM
Bought a gauge to check fuel pressure, but the reading was erratic and fuel accumulated inside the gauge. I assume the gauge was faulty, so I don't have an accurate pressure reading right now.
When cold, the car will start but then die immediately. If I press the gas, I can keep it running, and then it will idle (very rough) once it warms up for about a minute.
When I try to drive it, it stumbles up to about 2500 rpm. Above 2500 it seems smoother and accelerates decently.
April, 15, 2009 AT 6:17 PM
Well, if it were a fuel pressure problem, the symptoms would be the other way around. Good performance at low revs and poor at higher revs under load.
I'm assuming you have not had a "check engine light". A problem with the cam sensor will usually trip the CEL, but many times a bad throttle position sensor won't. I'll see if I can find the TPS test specs and attach them to this post. I now sounds like the TPS may have a dead spot in it.
April, 15, 2009 AT 7:58 PM
I do have CEL, codes P0300, P0301, P0302, P0303. Just misfire codes. Would a bad TPS cause misfires like that? Thanks for the spec sheet, I'll test the TPS as soon as I get some daylight.
April, 15, 2009 AT 8:14 PM
The term " miltiple missfires" mean that a given cylinder is not firing. This isn't just limited to spark. A lean condition can also cause a misfire. And, a possible cause of this could be the TPS. Let me know what you find.
AND, what do you mean, " get some daylight", it's still daylight here. Pardon my twisted humor.
April, 16, 2009 AT 9:57 AM
Sounds good, I'll check it out. My work schedule doesn't allow me much daylight : )
I'll post my findings.
April, 22, 2009 AT 10:19 AM
Ok, TPS was slightly off the numbers you posted. I replaced it and cleared DTC codes. Started it up and it ran (didn't stall immediately like usual), but still very rough. After a couple minutes the misfire codes came back (cyl 1 & 3)
Side note, I can hear what sounds like sparks arcing to the block intermittently. It will do it for 30 seconds, then stop for a minute, etc. I started the car in the dark and couldn't see any arcing.
August, 11, 2009 AT 4:36 PM
Did you ever find the problem? I'm having a misfire on my car and figured your solution may help me if you could just post the result.