Cold start issue

[Electricalbox]

Hello everyone, I have a cold start issue that when started the motor will begin to bog and kick really hard after about 10 seconds, unless I depress the throttle a bit (even for just like 5 seconds...a few revs) and it is ok. When the bogging happens I get a CEL which came out to be 1222 Lamba #1 IIRC. Normally I would think o2 sensor, but it runs fine after start up and/or warm starts. I cleaned the coolant temp sensor figuring it would be this or a vacuum leak, but I could not find the problem. Maybe fuel filter???

The reason I need it (other than the fact to rid myself of the annoyance of this throttle tapping) is that I need to smog the car soon. Any suggestions welcome, thanks so much and please let me know if I missed anything to check.

:) I <3 Bf.c ;)

[Bill R]

Which coolant temp sensor did you clean?




Hello everyone, I have a cold start issue that when started the motor will begin to bog and kick really hard after about 10 seconds, unless I depress the throttle a bit (even for just like 5 seconds...a few revs) and it is ok. When the bogging happens I get a CEL which came out to be 1222 Lamba #1 IIRC. Normally I would think o2 sensor, but it runs fine after start up and/or warm starts. I cleaned the coolant temp sensor figuring it would be this or a vacuum leak, but I could not find the problem. Maybe fuel filter???

The reason I need it (other than the fact to rid myself of the annoyance of this throttle tapping) is that I need to smog the car soon. Any suggestions welcome, thanks so much and please let me know if I missed anything to check.

:) I <3 Bf.c ;)

[Electricalbox]

cleaned both of the sensors in my thermostat housing. :)

[Bill R]

I hope that we're both referring to the electrical contacts and plug rather than the probe on the sensor...




cleaned both of the sensors in my thermostat housing. :)

[janders211]

If you aren't blowing black smoke it's probably running lean (guessing-since it's doing it cold when the car normally runs a little leaner to warm up).

Clean your MAF, and check your fuel pressure for easy fixes, and I guess since fuel filters are cheap it can't hurt to replace it, but I doubt that's a problem if the car runs fine under load, at higher RPM.

I hate that too lean, and too rich both pop the same codes.

[Bill R]

He doesn't have a maf, has an afm.




If you aren't blowing black smoke it's probably running lean (I hate that too lean, and too rich both pop the same code).

Clean your MAF, and check your fuel pressure for easy fixes, and I guess since fuel filters are cheap it can't hurt to replace it, but I doubt that's a problem if the car runs fine under load, at higher RPM.

[Electricalbox]

I hope that we're both referring to the electrical contacts and plug rather than the probe on the sensor...
:helpcrap, was I not supposed to get the residue off the sensor? PS the car works fine just a quick blip in the start up issue...it was cleaned with 800 grit sandpaper until it was clean.

It just seems so weird that it happens quickly and can be eliminated quickly, but I just don't want any chance of it failing. :D

[Bill R]

in the past on my own 535 i had a similar issue that was a momentary short time period after start up and it ended up being a poor connection on the temp sensor. I cleaned up the terminals on the sensor and the connector with some deoxit d5 then treated them with stabilant 22 , never again a problem.





:helpcrap, was I not supposed to get the residue off the sensor? PS the car works fine just a quick blip in the start up issue...it was cleaned with 800 grit sandpaper until it was clean.

It just seems so weird that it happens quickly and can be eliminated quickly, but I just don't want any chance of it failing. :D

[LouieD]

Mine does the same thing, if I don't let it warm up a bit. I haven't really haven't made it a priority though... I don't think it will effect your smog test... 'cause they run that after the car has been thoroughly warmed up. I failed mine because of high Nox, and I still have to go back, I think I have a bad O2 based on some research and testing, I just have to replace it and get it inspected again.

Keep us posted as to what you find out.

[Electricalbox]

For sure, thanks for the replys everyone... Hope to get this figured out this weekend, along with many other projects :)