Black smoke?

[Blue 88]

Not sure if this is where this goes or not, but I recently traded a 88 ranger with a 2.9. When I crank it up and it is cold while driving down the road it feels like it is falling on its face and misfireing? If I crank it and let it warm up its ok. But when its cold it sputters and I see black smoke out of the exhaust, i know that usually means its to rich, but it goes away once its warmed up? Any help would be greatly appreciated!

 

[creepinjeepster]

Have you checked TPS sensor? IAC sensor? Air filter? by the sounds, it may be trying to high idle to warm up, but not getting the right fuel/air mixture. Would check on the air side for anything clogging it or a bad sensor as above.

 

[Blue 88]

The air filter is a K&N w/o the box. No I havent checked those sensors but will do it now thanks for the input. Anymore will be appreciated.

 

[creepinjeepster]

Do you have manual or automatic choke? Might have neither. Carb or fuel injected? can't remember with that year truck.

 

[Blue 88]

It is a fuel injested 2.9

 

[Blue 88]

SORRY It is a fuel injected 2.9

 

[creepinjeepster]

Wold almosst guess your IAC. Do you know how to test?

 

[Blue 88]

No I was gonna ask some of my friends but if you dont mind telling me that would be great!

 

[creepinjeepster]

To check the IAC, with engine running, unplug it. The idle should drop, but not die. then plug it back in. The idle should rev up to around 1000-1500 for a few then idle down to normal idle. If it dies when unplugged or doesn't change idle at all during the test, the IAC is bad and needs replaced. There are some people that would say pull it off and clean it and try again, but you can mess the IAC up by cleaning. Newer ones are even marked with the warning now, so my recommendation is to just get a new one if it fails the test.

 

[Blue 88]

Not to sound like a complete idiot but what is the IAC? and where is it located?

 

[creepinjeepster]

IAC stands for Idle Air Control Valve. On the 2.9 it is located on the left side of the air intake plenum as you're looking from the front of the engine. It will have a harness with two wires that plug into the back of it. One wire red and the other I can't remember the color of. It is just past the vacuum tree on that side of the engine too.

BTW, your not sounding like an idiot. Everybody has to learn somewhere right? Dumbest question is the one never asked.

 

[Blue 88]

Thanks for the awesome tips

 

[IMenriched]

Also check the temp sensor....the one for the engine computer , not the one for the dash guage

 

[robertc1024]

Hey Creepin' - not to hijack the thread but - are you sure about if you unplug the IAC the engine shouldn't die. I've been having a high idle issue and somebody else posted on my thread that it should die. Not trying to diss you - I'm just confused?

 

[modelageek]

a few thoughts . in the 1988 it might aka an idle air bypass valve, I cleaned my iac valve and it worked better. why not try and clean it if it doesn't work get a new one. you clean it with electriclal cleaner . I used carb cleaner,some peeps dont like using that. have you tried to pull any codes for the truck, how about cahanging plugs, wires, etc, I was reading this morning about people who use "restore" in there oil, most of the posts were positive.