Outer Limits 4x4 Board

Ok so I think my exhaust manifold gasket is damaged. Car is running like a pig, is there a way to 100% diagnose this without pulling it off just incase this isnt the issue.

Put a tissue above the manifold and look for it to blow from the exhaust gas or soap and bubbles

cheers mate, very simple, i love it.

if its diesel look for sooty marks around the manifold, it wont take long to leave a sooty mark if you have leaks.

another thing you can do is use a piece of hose as a stethescope, hold one end in a closed fist with your fist and the end of the hose against your ear, hold the other open end beside the exhaust manifold joints and move it around the joints, if it passes over a leak, you should hear it through the hose

Well its not the exhaust side. There is cracks around where the air filter box connects to the air flow meter so i taped that up as a quick fix and it didnt make any difference so its not that either. Think it may be the inlet side.

How do you tell if the airflow meter is stuffed.

stilivn wrote:. Think it may be the inlet side.

if it's the inlet side, spray some wd40, or aero start, or whatever burns around the joints while the car idles. if the idle speeds up, you know where the leak is

bad_religion_au wrote:

stilivn wrote:. Think it may be the inlet side.

if it's the inlet side, spray some wd40, or aero start, or whatever burns around the joints while the car idles. if the idle speeds up, you know where the leak is

Yeah done that an no idle up. Do you test the airflow meter with engine on or off. When the engine is off it returns 3.9 volts which is good but when its on its reading 1.4.

Ok what I know. It is running lean, car is fitted with a sensor for lpg. It isn't a fuel delivery issue as it runs rough on both lpg and petrol. Still trying to find info on testing afm. I havnt checked plugs or leads yet but don't think that is the issue. I tried spraying wd40 around the intake manifold but couldn't say 100% that I have ruled that out as its too hard to get too. No hoses are split or loose. Anyone got any suggestions.

Check the plugs first mate. On LPG if you dont use the correct heat range plug it will deteriorate them pretty quick.

Northside 4x4 wrote:Check the plugs first mate. On LPG if you dont use the correct heat range plug it will deteriorate them pretty quick.

If it was the plugs wouldnt it be running rich? will check in the morning, only 11 months old but were off flebay so could be the issue. Got a working second hand airflow meter the other day so when that arrives I will try that also.

How do you know its running rich? have you put an AFR meter on there to check it?

Its not, its running lean. There is a unit installed with the lpg to check how its running and it says lean, hence me thinking too much air mixing with the fuel. Same symptoms on petrol so its not cause not enough fuel is getting through.

Northside 4x4 wrote:Check the plugs first mate. On LPG if you dont use the correct heat range plug it will deteriorate them pretty quick.

close enough, pulled the lead off the dizzy and the other end was rusted to the s-house. One of the spark plugs I tested wasnt working too so I replaced all leads and plugs, $180 later, could have done that on my ute for under 50 buck, oh well it is the first time I have changed the leads in 4 years so I cant complain.

Thanks to all those who made an input, cheers.

stilivn wrote:

Northside 4x4 wrote:Check the plugs first mate. On LPG if you dont use the correct heat range plug it will deteriorate them pretty quick.

close enough, pulled the lead off the dizzy and the other end was rusted to the s-house. One of the spark plugs I tested wasnt working too so I replaced all leads and plugs, $180 later, could have done that on my ute for under 50 buck, oh well it is the first time I have changed the leads in 4 years so I cant complain.

Thanks to all those who made an input, cheers.

And that fixed the problem?

yeah mate runs smooth as, amazing that it made such a difference or problem in the first place.

stilivn wrote:yeah mate runs smooth as, amazing that it made such a difference or problem in the first place.

Good to hear !