3rd Generation Honda Prelude Common Problem Fixes
Posted: Mon Mar 31, 2008 1:01 pm
Hey everyone,
I thought I would start compiling a list of common fixes for the Honda Prelude.
Bouncing (Fluctuating) Idle
It's very common to hear of a Prelude that has a bouncing idle problem. What usually happens is that once the car warms up, the idle will fluctuate in between about 750 rpm and 1500 rpm whenever the engine isn't under load. This can be very annoying.
In my experience, 90% of the time this problem is caused by a faulty Fast Idle Valve. Inside the Fast Idle Valve there is a plunger that moves up and down dependent on the engine temperature. When this plunger stops working correctly, it will often cause the engine rpm to fluctuate.
To fix this problem, start by unscrewing the cover on the Fast Idle Valve (located on the firewall side of you intake plenum, bolted near the throttle body). Look inside and use a large flat head screwdriver to verify that the plunger inside is screwed in all the way. Replace the cover.
If there is still trouble, re-bleed your engine coolant system. The Fast Idle Valve relies on the coolant temperature for proper activation. If your coolant system hasn't been bled well you may have problems.
If the idle still fluctuates, replace the Fast Idle valve. You can get a new one from Honda, or if you can, save some money by purchasing one from an auto wrecker. Additionally, it is possible to buy a Fast Idle Valve on Amazon
Note: As an amazon associate, I earn from qualifying purchases.. Be sure to check fitment with your Prelude model before purchasing though.
I thought I would start compiling a list of common fixes for the Honda Prelude.
Bouncing (Fluctuating) Idle
It's very common to hear of a Prelude that has a bouncing idle problem. What usually happens is that once the car warms up, the idle will fluctuate in between about 750 rpm and 1500 rpm whenever the engine isn't under load. This can be very annoying.
In my experience, 90% of the time this problem is caused by a faulty Fast Idle Valve. Inside the Fast Idle Valve there is a plunger that moves up and down dependent on the engine temperature. When this plunger stops working correctly, it will often cause the engine rpm to fluctuate.
To fix this problem, start by unscrewing the cover on the Fast Idle Valve (located on the firewall side of you intake plenum, bolted near the throttle body). Look inside and use a large flat head screwdriver to verify that the plunger inside is screwed in all the way. Replace the cover.
If there is still trouble, re-bleed your engine coolant system. The Fast Idle Valve relies on the coolant temperature for proper activation. If your coolant system hasn't been bled well you may have problems.
If the idle still fluctuates, replace the Fast Idle valve. You can get a new one from Honda, or if you can, save some money by purchasing one from an auto wrecker. Additionally, it is possible to buy a Fast Idle Valve on Amazon
Note: As an amazon associate, I earn from qualifying purchases.. Be sure to check fitment with your Prelude model before purchasing though.