88 stalls when put into reverse

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skyaugen

NAXJA Forum User

Location

new jersey

• Jun 26, 2010

• #1

My 88 4.0l auto started up fine, idled normal and drove about a mile to the gas station.At the station I had to put it into reverse to get to the pump and it stalled. When I started it back up and got stuck in high idle around 2500
rpm and wouldn't go down.This happen before a week ago also, it that time I
torque the intake and exhaust bolts and adjusted the TPS and it ran fine, but
now it's back to high idling again when I started it up.

 

joe_peters

NAXJA Forum User

Location

Grants Pass, OryGun

• Jun 26, 2010

• #2

Check to see if the throttle plate is hanging up and remaining open.

I would suspect you have a substantial intake leak somewhere--intake gasket, vacuum lines, brake booster line. Start plugging things off until you get a change in idle.

Engine off, unplug the IAC and start it up.

 

old_man

NAXJA Forum User

Location

Loveland, Colorado

• Jun 26, 2010

• #3

A stall in reverse is commonly associated with a CPS cable that has gotten next to the exhaust manifold and melted through. The other symptoms don't really track.

Double check your ground from the engine to the firewall.

 

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skyaugen

NAXJA Forum User

Location

new jersey

• Jun 26, 2010

• #4

Tried the unplugged IAC and got no change, also the CPS cable is fine. Check for leaks
next!

 

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stephenspann27

NAXJA Forum User

Location

College Station, Tx

• Jun 26, 2010

• #5

anyway it could be NSS related?

 

joe_peters

NAXJA Forum User

Location

Grants Pass, OryGun

• Jun 27, 2010

• #6

stephenspann27 said:

anyway it could be NSS related?

Click to expand...

I don't think its the NSS, that has multiple functions--engine will only crank in PARK and NEUTRAL, it also provides a mechanical input to the TCU of which gear is physically selected--but it can't kill the engine or effect idle speed.

 

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skyaugen

NAXJA Forum User

Location

new jersey

• Jul 8, 2010

• #7

Finally got around to checking for leaks and couldn't find any and still had a high idle.
So I thought it I might check the IAC even though I put a new one in two years ago.
I kept the old one just to have as a spare and sure enough it started up fine and went to a normal idle when I put the original one in.
Anybody know were I can get a new IAC that will last longer than 2 years, not like the
one I got from napa.

 

joe_peters

NAXJA Forum User

Location

Grants Pass, OryGun

• Jul 8, 2010

• #8

I would hit the salvage yards and pick up two or three--cheap, and odds are most of them will be good.

 

87manche

NAXJA Forum User

Location

Ohio

• Jul 8, 2010

• #9

it may also be that the napa one isn't bad, just that it was stuck in some nasty carbon. I have the occasional high idel on both the 87's, taking out the IAC and cleaning it's bore always fixes them. I have yet to replace one of the 20 year old IACs, just clean them.