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1989 Wrangler stalls when brakes are used.

When I use the brakes on my 1989 Wrangler 4.2L 5-speed the engine stalls. It doesn't happen during idle and the brakes are used, just when coming to a stop while driving. When I am driving and I put the clutch in, the engine idles fine. It's only when the brakes are used. At idle, if I twist the steering wheel side to side, it loses a few RPM, but nothing like how the engine just dies when the brakes are used. I've tried moving the idle up to 20,000 RPM, but it doesn't help, the brakes just pull the RPMs down low enough to stall the engine. The carb is running a little rich but not bad. Brake fluid looks good. The engine has over 165,000 miles on it. Oil pressure is up towards 80 during idle and driving, but sinks quick when brakes are applied while driving.

I'm going crazy over this.

Any ideas why this is happening.

Thanks!

-Mark

Reply to
Mark12211
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That implies a sticky EGR valve to me.

The EGR opens at speed and if it closes to slow, it dies when braking.

You can disconnect and plug the vacuum line to it to see if that makes a difference. If so a good soak in carb cleaner can free them up after you remove it.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Mark12211 wrote:

Reply to
Mike Romain

Reply to
L.W.(ßill) Hughes III

Not familiar with that model, but would it by any chance use vacuum assist for the brakes?

If so, the vacuum boost probably has a pretty good leak when the pedal is depressed, causing extreme leaning out.

An even more obscure cause could be something in the brake light sensor shorting out enough to drop the ignition?

Mike Romain proclaimed:

Reply to
Lon

for any one following the thread.... I had to drop the Jeep off at the shop to be looked at. It ends up it's a bad carb, leaking inside.

Thanks for everyone's help.

-Mark

Reply to
Mark12211

Reply to
L.W.(ßill) Hughes III

At least a carb kit is only $20.00 or so for that carb. The kit comes with a new float needle and seat to stop the leaking.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Mark12211 wrote:

Reply to
Mike Romain

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