Honda Prelude Forum - PreludeDriver.com

I bought a 89 prelude 2.0S with 88000 km a month and a half ago from an old dude. When i first got it i replaced the alternator, battery, put NGK wires and plugs. After driving it a bit it started running rough and loosing power at higher speed so i got the fuel pump (with primary & secondary filters) replaced at AutoPro. Replacing the fuel pump fixed that problem.

Now i have an other problem, when the car is in park the idle is fine but when i get it hot and brake to a stop while its in drive the rpm goes way down to 150-200 and eventually stalls if i don't press on the gas. After it stalls it only starts after cranking on it like a maniac while pumping the gas pedal. Thats always fun when it happens in rush our traffic. The guys at AutoPro played with my carbs when they changed the fuel pump and i made them check it again and they say its fine.

So does anybody know what could be the problem??

Thanks

Hey Inferno,

First of all, welcome to PreludeDriver. We're glad you found us.

I've had the same problem on my 86. One time the car stalled at a Red Light and I actually had to push it out of the intersection because I couldn't get it to start again.

In my case, the problem was with the coolant temperature sensor. It's the two-wire sensor that is in your thermostat housing (engine end of the upper radiator hose).

As a simple test, get your car warm to the point where it starts idling really badly and then unplug the sensor. Your idle should come up. After I replaced the sensor, my problem went away. As a safety note, don't unscrew the sensor while the engine is warm as the coolant will be very hot.

I don't think coolant temperature sensors are that expensive. I got one from a wrecker for about $2 and haven't had a problem since.

Thanks man ill replace the sensor tomorrow and and see what happens!

Peace

hey spiffyguido,

Finally it was the left carburator cutoff solenoid. Changed it and now runs perfect!

Great to hear. Way to go!