I have a 2000 Honda Accord (VTEC SE auto) with 65,000 miles on it. The car was converted to lpg (dual fuel) before I bought it.
The car will not idle properly at any point under either lpg or unleaded. It appears to be a basic vacuum or timing problem, but two mechanics (lpg installers) have now given up on it. There are no fault codes, and as far as I'm told, the MAP sensor is fine. The cylinders seem to have good compression and had no leakage either.
Today the car went to the Honda dealer who rang me back a few hours later to say that there are no fault codes, so I should take the car to an lpg specialist.
I really feel like I have a good car with a fixable problem. But after 3 months of trying with no results, I'm beginning to lose hope.
When you say idling properly, is it surging up and down without a constant rpm? Explain the idling more please. If it is surging, I would check for a leak at the intake manifold.
September, 26, 2006 AT 7:51 AM
When stopped at traffic lights, etc. The idle falls quickly below 500. Sometimes it stalls immediately and sometimes it just barely ticks over. Left without any help from the throttle it will stall.
As you would guess, the vacuum in the engine is very low (or non-existent) but actually finding a leak or obvious timing problem is turning out to be a huge challenge.
I am told that the engine is burning very little of the fuel going into it (because we can see very high emissions on the exhaust). One mechanic who has spent some time with the car agrees that it could be the intake manifold, but he could not find any reasonable info about how to troubleshoot that system.
Thanks for the reply.
September, 26, 2006 AT 1:00 PM
It is really quite simple, test it with smoke. A smoke test will tell you if there are any leaks. They test furnaces this way using a special type of smoke bomb. I have performed it on vehicles to detect vacuum leaks and bad intake manifolds and gaskets.
September, 27, 2006 AT 4:04 AM
That's an excellent idea Bruce. Thanks for that!
Can you elaborate a bit about your technique for doing this? Do you just send the smoke in through the air intake and then simply look for leaks?