Engine Ping/ Fuel Smell

[Katen]

I have a 1996 Q and it has Engine Ping when its hot out, also have gas smell coming from engine compartment. Its not all the time i smell it, but when you do its enough to make you want to get out. I have noticed that its comming from the left bank towards the front. Any ideas on what that could be, and whats causing the ping. I run 91 octane.
Any help would be great.
Thank You
Ken

[Q451990]

Given the location of your fuel smell, I would take a look at the carbon canister. The ping could be a timing issue, clogged EGR, improper spark plugs... that's a hard one to track down.

If you haven't done so, check out your factory service manual at www.nicoclub.com/FSM/

Heath

[elwesso]

Do you hear the pinging at idle?

[Katen]

No, its only durring excel and pulling hills, doesnt do it much in the colder season, once it starts to warm up its really bad. We had 107 temps yesterday and it was really bad it gets to 120 out here in az. im changing the plugs today to colder ones. will let you know

[elwesso]

There shouldn't be much reason to go to colder plugs, I'd really be more concerned you've got some nasty carbon buildup. I'd be thinking about running some seafoam through the engine or something like that, and then running the crap out of it. Has the timing ever been messed with?

Has the car been used mostly for short trips and driven easy? IF so the carbon buildup could really be causing that.

[Katen]

Did top engine clean with GM stuff and i drive the puss out of it, and as far as timming i dont think anyone has been there

[Q451990]

How about your EGR valve? Is it functioning and has the port between it and the plenum been cleaned lately? If not, you can get a lot of nasty carbon buildup that would block it from functioning.

Heath

[elwesso]

Yeah that's a good call too. The EGR is probably caked solid if it hasnt ever been cleaned. I'm wondering if the knock sensors are good?

[Katen]

Yeah that's a good call too. The EGR is probably caked solid if it hasnt ever been cleaned. I'm wondering if the knock sensors are good?

Will have to check the EGR, no MIL so who knows if the sensors are working.. Any way of checking them and the EGR without removing??
did another top clean, with no luck

[Katen]

Took EGR off and it looks good very little build up cleaned and reinstalled still have ping, waiting for plugs to come in, btw I have the hook-up on these $14.00 plugs

[Infinitiguy19]

Anyone bypass the knock sensors?

[Q451990]

The carbon build-up is usually inside of the plenum, not in the EGR valve. It's pretty difficult to clean without removing the plenum. I use dental picks, drill bits, all kinds of fun stuff to pick the carbon out. There's a 90 degree turn right before it goes into the main body of the plenum, so a lot of it builds up there.

Heath

[Katen]

Sent a scope down the plenum its all good very little build up

[elwesso]

What heath is saying is the carbon in the EGR happens in the passage where the EGR valve bolts to the plenum. The best way to see how things are is to take off the Throttle Body. You can get things pretty clean by taking off the TB and the EGR valve, as the EGR discharges through a little hole just behind the TB. Unless the plenum has been taken off, the EGR passage between the EGR valve and TB is probably nearly caked full.

[Q451990]

The hole marked in red is where the EGR comes into the plenum. The green arrow shows where the temps sensor screws in (or on earlier non-CA models a block-off bolt).



Heath

[Katen]

Thanks for sll the info, its fixed, with new pfr6g11's scoped the piston tops and where clean , also scoped the plenum and all ports and holes are clean..

[Q451990]

Awesome!