'89 Ranger -- Intermittent loping idle and stalling

[tachnem]

'89 2.3 5spd. Started loping last week and I had to park it. Trying to take a look at it now. 215k on the clock, don't know much on it's history. The loping is intermittent though. Sometimes I'll start it and it will idle fine for about 2 minutes, then start loping. Other times it'll idle erratically from the start and eventually die. The CEL comes on when it starts loping, but no codes. All I'm getting is 11. I've tried with motor running and off.

While it's running rough, if I pull off the black vacumn hose on the vacumn distribution fitting that runs to the T at the big capsule looking piece, it will smooth right out. Or, if I pull off the red vacumn hose that runs to the EGR switch, the idle will also smooth right out.

Any ideas are much appreciated, hoping not to throw a bunch of money into it.

Thanks,
Sean

 

[mnmattie]

first instinct would be to clean/replace the egr if you pull the vacuum hose off and it smoothes right out.

-mattie

 

[tachnem]

Pulling the green hose off the egr directly did nothing for the idle, but I did go ahead and pull it off anyways and clean it. Still no difference.

Thanks

 

[TooManyRangers]

use some carb cleaner to check for vacume leaks. spray in an area and listen for a change in idle speed. pay close attention to intake manafold at the head and all vacume lines. also check you brake booster. a simple way to check that is to start the engine for 30 seconds. turn it off without touching the brake pedal. pop the hood and after 20 to 30 seconds pull the vacume line off of the booster. if there is a good amount of vacume it is probably fine.

 

[tachnem]

Thank you very much for the tips, I'll try that.

I may be thinking about this wrong, but doesn't the fact that the idle smoothes out when I pull a hose lead to the possibility of blockage somewhere?

Seems like if I had a vacumn leak, and then pulled a hose off completely, it should get even worse???

Thanks again
Sean

 

[backerm]

not neccesarily, the computer is probably compensating for it, it thinks that your stepping on the gas.