machine23

does anybody else have this problem?

so im driving on the highway, going 40 or so. i come to a red light so i start slowing down. as soon as i put my transmission into neutral and release the clutch my engine rpms go way down. to about 200-400 rpm. and the needle bobs there for about 5-10 seconds unless i tap on the gas pedal. the engine feels like its wanting to die when this happens. i lose a little bit of braking power too because the engine isnt producing adequate vacuum for my power brake booster.

and i cant get the engine to do this from just moving the butterfly around with my hand on the throttle body. anyone have any idea whats going on?

Tubbyfatty

Motor brake instead of just using your brakes, you save brakes that way.

Look for a big vacuum leak. Im guessing that could be the problem you have.

San Martian

Im 99% sure its the EGR, I just had this problem last month. Block it off, I put this little black cap on and fixed the problem right away.

machine23

what makes you so sure its the egr valve?

Speedy_McTall

I have exactly the same issue. I'll be watching for the fix and I'll post if I find one. I'll try the egr thing and report back.

machine23

well guys last night i was heading home from work and i got the feeling that i should watch my engine bay while it was dark outside to check for any little bolts of lightning going on. and it turned out that i have some bad spark plug wires. big time. its cool to watch though.

so this may solve my rough idle issue. we will see!

Tubbyfatty

Only use Denso or NGK products. Might as well get a cap, rotor, plugs and wires.

Cap is like $10
rotor is like $5
plugs are $3 a piece (alot of people run NGK v or g power)
NGK wires are $50, well thats what I paid for em at Napa

machine23

yea i know the prices. im an o'reilly parts guy. my plugs looked fine but my wires are definitely going to be changed. ill just stick with the bwd spark plug wires so i can smog my car. and later when i have some cash i will throw on the better wires from toyota

machine23

i put on the new wires and it is still doing the same thing...

machine23

well guys my car got towed yesterday due to 6> registration expiration....but i never figured out my rough idle/misfire problem. but there was one thing i saw...i noticed that my throttle body was leaking water directly onto my knock sensor connector...so about 3 hours before it got towed i decided to unplug that connector to see if maybe that was shorting out due to water. i did see some moisture and liquid inside there....what sucks is i was never able to test drive it . soooo.....moral of the story is...dont drive your car around when the registration is expired over 6 months.

Speedy_McTall

Ok well I finally got around to removing the hose for the EGR valve. I plugged one end of the hose with a pencil eraser "extension" (the kind that fit over a pencil) and left the other on the hard line.

I took her out for a drive and the RPM's no longer drop when braking! Fix worked perfectly! RPMs remain a rock steady 750 when warm and don't dip or anything now.

Thanks for the fix!

TJ96TLC

A little more explanation needed..I noticed last night that when I push the brake at idle, or when stopping, the idle goes down. Am I understanding this that I should plug off the EGR valve, or replace it??? 1987 4Runner 22re 4x4