Reoccuring p0303 code
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From: georgia
Reoccuring p0303 code
2002 Lexus LS430 - 200,000 miles
- Oct. I replace all ignition coils and spark plugs.
- Nov. I get a p0121 code, I replace the TPS and calibrate it to 15.3%. It has settled to 14.9% with power on, engine off if that matters.
Shortly after replacing TPS, I get the p0303 code. It would idle poorly at stop signs, red lights, etc. but drive decent enough. I've switched out the coils 3 and 5. When I start the car, the engine idles badly with flashing CEL with code p0303. I checked the spark plugs and coil for cylinder 3 which all seemed fine.
Could all this be coming from a faulty TPS? Any way to check for bad fuel injector?
- Oct. I replace all ignition coils and spark plugs.
- Nov. I get a p0121 code, I replace the TPS and calibrate it to 15.3%. It has settled to 14.9% with power on, engine off if that matters.
Shortly after replacing TPS, I get the p0303 code. It would idle poorly at stop signs, red lights, etc. but drive decent enough. I've switched out the coils 3 and 5. When I start the car, the engine idles badly with flashing CEL with code p0303. I checked the spark plugs and coil for cylinder 3 which all seemed fine.
Could all this be coming from a faulty TPS? Any way to check for bad fuel injector?
Thread Starter
Driver School Candidate
Joined: Oct 2015
Posts: 42
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From: georgia
Thread Starter
Driver School Candidate
Joined: Oct 2015
Posts: 42
Likes: 0
From: georgia
I'll be very happy if I were to fall victim to that particular issue. Hopefully a new connector solves the problem.
Last edited by kimsey; Dec 24, 2018 at 06:50 PM.
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Driver School Candidate
Joined: Oct 2015
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From: georgia
Update: I'm a dumbass, I clipped the connector on cyl. 5 but forgot to do so for 3 and it gave me code p1310. After checking my work, no codes after driving for a good 15 min. or so.
Appreciate RW and 911 for their suggestions. While inspecting the 4 wires from each connection, they all seemed in good condition. I sprayed some CRC electrical cleaner on them.
Apparently the connector housing was faulty even though there was no apparent signs of damage. Would have never guessed it to be the problem, and was going to chase the injector instead. I'm going to change all coil connectors and advise everyone to do the same, thank for everyone's input.
Appreciate RW and 911 for their suggestions. While inspecting the 4 wires from each connection, they all seemed in good condition. I sprayed some CRC electrical cleaner on them.
Apparently the connector housing was faulty even though there was no apparent signs of damage. Would have never guessed it to be the problem, and was going to chase the injector instead. I'm going to change all coil connectors and advise everyone to do the same, thank for everyone's input.
Last edited by kimsey; Dec 29, 2018 at 12:27 PM.
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From: FL
May I ask what brand of ignition coils did you install in your ls?
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