Prado VZJ95R 3.4l Petrol/LPG

[[email protected] Lurker Find all posts View Profile Close [email protected]]

Hi Guys,
I'm new here and would like to ask a question. What would cause this issue ?

I was driving along and came to a stop at some traffic lights, Prado was using LPG and when i took off got to about 2000RPM and heard a bang (like a misfire) so absolutely crapped my pants and slowed down abit then accelerated again then bang at 2000RPM so i pulled over popped the hood and pulled the accelerator cable sure enough the Air Cleaner Lid had blown off and the inside broke out of it and the intake pipe blew out of the clamp. At this stage i have turned off the LPG and put it back on Petrol and it seemed to idle fine but when i drove off it now has a shudder in the engine. Any ideas please ???

cheers Mick.

[Esses Junior Member Find all posts View Profile Close Esses]

I've had this happen in LPG courier vans. It's a backfire through the throttle-body which is why the air-cleaner got a kick. It means that either the tune was out or the engine worn. The "shudder" in the engine might well be an air-leak in that intake tract somewhere. Check all the hoses & clamps to make sure they're all tight & in place. Also check for cracks or holes in the various plastic bits. If the backfire was bad enough it MIGHT have done some damage to the throttle-body or valves, but hopefully not. Good luck with it.

[ken2m Junior Member Find all posts View Profile Close ken2m]

Also check your plugs and coils as that could be the cause of the initial backfire. It is most likely a faulty plug. Replace with multi point plugs if they aren't already. The engine will usually tolerate a weak plug on petrol but not at all on gas.

With the rough idle the regular ones that would give me grief were the one from the manifold to near the power steering pump, and the other one was on the carbon canister. One that was hard to trace and only happened once was a sort rubber hose at the rear of the curb side rocker cover that is connected to the thin steel tube that runs across the top of the manifold. Hope this helps. Ken.