Topic: Prob when idleing

[Johnny5]

Hi there i am working on a 93 toyota 22re 4x4. prob is is runs rough when idling but smooths out perfect as soon as engine speed increases. at idling if i unplug the vacuum line to fuel pressure reg it smooths out some. the exhaust stinks too but has had a new cat installed and oxygen sensor doesn't throw a code.timing is spot on adn engine doesn't blow black smoke so i don't think its overfueling.  looking for ideas what else to check for

[Goldrush]

ur throttle sensor???

[silence007]

keep that vaccum line plugged then put a vaccum pump on the regulator.  Sounds like a valid start.  Regulator could be bad.  Look up trouble tree on correct diagnosis of that regulator.   could be too rich and the new cat is catching all the black, too rich is the only thing to kill a cat.  besides rocks of course.

[Tallchevy]

My 22re ran the same way. I found that 1 of the injectors wasn't firing. I found that by pulling off the spark plug wires off 1 at a time until the engine idled the same with the spark plug wire was on or off.

[Johnny5 [OP]]

i,ve changed regulator already and same thing. i agree its over fueling but why??tried a diff comp also no different i have another set of injectors to try but i will try the sparkplug trick 1st

[2manytoys]

My son's 91 22RE is doing the same thing. We couldn't find any vacuum leaks at first but I finally found the rubber grommet that seals the rear injector @the intake sucking air.

Found it by squirting WD-40 or carb cleaner (don't remember which) directly at the grommet. The idle changed noticeably when the stuff hit the leaky area.

First time I've ever had those leak. Just something else to check.

[Johnny5 [OP]]

well i've changed the intake rail and injectors still no change. i do know #4 is the prob cylinder as intake runner is soaked so over fueling. plenty of spark and tried a diff sparkplug no change. know pulling the vac line no change now so still looking

[silence007]

Now do a compression test, if that cylinder passes do a cylinder leak down test.  with all the stuff you have done and passed I can only see low compression on that cylinder causing misfire.

[954toy]

i agree. check for the compression. maybe some brakekleen and spot check as well.