car runs starts and runs fine untill about 20mins riding

[tmaiii]

ok, as stated in the title my car starts and runs normal when it is first started. idles, accelerates and runs great... until about 20 minutes into a ride then it idles very roughly. I would have to keep my foot on the gas a bit to keep the car from stalling out.

the original engine had a head gasket blown so i had a 5th gen motor swapped in, it was a f22b2 i think. what I've done so far to try and remedy the problem has been: plugs, plug wires, cap, the whole distributor, fuel filter wasn't to long ago, cleaned the egr, iacv, re soldered the main relay.... couldn't fix the problem. a friend told me it may be the fuel pump? i need some input on this, and hopefully it could fix my problem. again the engine runs like normal and idles fine until about 20mins into a drive. Thanks in advance

[Gotz Cb7]

Have you tried adjusting the idle? It's gonna idle high at first, but after the car warms up, the idle should be around 600-800rpms? After cleaning just the IACV, I had to re-adjust my idle. You seem to've done a lot more. Check it out.

[tmaiii]

yeah i did adjust the idle, car is warmed up and idles fine at 800. it does run and idle fine at first but for some reason when it runs a little longer something would just go bad and make the car idle very roughly . oh forgot to mention that there is a smell of gas when it does start to idle rough.... you can smell it from the back of the car from the exhaust and then into the car cabin.

[black sunshine]

had the same thing awhile back, changed the alternator, and it was fine.
look into that

[tmaiii]

could it be the alternator? and what would cause it to do that?... but ill look at some prices

[be3p067]

Do you get a CEL when this happens? sounds to me like one of your cylinders stops firing, have you ever tried pushing down on your plugwires when this happens. Used to happen to me.

[keycb7]

happened to me when i took off my valve cover and after puting beck forgot to put that smaller vacum line to it, after short drive on stop light my car stalled. so the problem was vacum leak. check for that.

[tmaiii]

truthfully..... the CEL light has been on ever since i got the car! =X which has been about 2 years now. motor was swapped into the car about 9-10 months ago? and it was left behind in new orleans when we had to evacuate from the storm.... sooo yeahhhh. its been through some sh!t, ive tried to check the code by the blue connector on the passenger and nothing happens. i could also believe that a cylinder stops firing... but dont know about pushing down on the plugs. if i leave the car to cool off in about 3 hours the car will run fine again

as for vacuum leak, the car runs normally for a good while and then starts to idle rough. if i gas it and go it would accelerate and run fine, its just the crappy idle it gives me. im trying to blame something electrical for causing this

[tmaiii]

help?

[king_cobra]

first things first. fix the CEL problem. if you can't pull codes, then you might want to consider swapping the ecu. you will never get your car to run right until that CEL issue is resolved.

perhaps the 5th gen motor requires a 5th gen ECU?

[tmaiii]

question, my previous ecu never gave me a code when i jumped the connector but i changed it. so this other one gives me only long blinks and keeps on going. i would assume it telling me that its #10 and keeps repeating right?

[tmaiii]

just to follow up on things. ecu didnt give me a CEL code because it was bad, so i changed it to another one. New one gave me a 10 which was the intake air temperature sensor. Changed the sensor, now it runs fine. so the problem all that time was the iat sensor. have a nice day

[bigjoegood1]

glad you got it resolved.

[deevergote]

Thanks for sharing the resolution as well... It helps to know what fixed a problem, when someone else comes along with the same problem!

[hondaguy305]

tmaiii do u have a pic of the Air Temperature Sensor?