1994 Ford Aerostar Could this be a Vacuun Modulator issue?

AERO1

MEMBER
1994 FORD AEROSTAR
6 CYL
2WD
AUTOMATIC
198,000 MILES

This van has been running fine with no problems whatsoever. Was driving one day and noticed coolant temp gauge fluctuating (apparent t-stat problem), about 5 minutes after I noticed that, I thought I saw whitish smoke (looking back via my rear view mirror). Lasted about 3 - 4 seconds. Next day, gears would take a few seconds to engage when shifting lever. This only when engine cold. Ok when warmed up. No tranny fluid leaks on ground and check of fluid over past week didn't seem to reveal problems. Van was driving great yesterday when started disengaging (gear) while driving. Would engage with a thud when punching accelerator. Did this all the way home (engine warmed up). This morning, trace of tranny leakage on ground in driveway (underneath tranny) and dipstick shows empty. No trace of fluid in throttle body. Modulator problem?

1 Reply

JGAROFALO

MECHANIC
489 POSTS

Very possibly. Look for the vacuum "tree" on the rear of the upper intake manifold. You can most easily reach this from inside the car with the "doghouse" cover removed. Find the line that goes down to the transmission, and disconnect it to look for evidence of transmission oil in it. Also check at the transmission end of the line. It is in a difficult place, as it is on the right side of the transmission and next to the exhaust pipe. If you see any oil in this line or dripipng from the vacuum fitting, then you do have a bad modulator.