Hi All

I've been having a problem with a mis-fire while running on lpg for the last
couple of months. I have gradually changed all of the ignition components,
plugs, coil pack, leads etc. and still have the misfire. It seems to run
quite smoothly on petrol but misses on gas, more so at the lower revs under
load than at the higher revs.
So I decided to do a compression test today. (had to buy a new compression
tester as I couldn't find the old gunsons one from ages ago)
cyl #1 - 12 bar
cyl #2 - 11.5 bar
cyl #3 - 11 bar
cyl #4 - 7 bar
hmmm looks like a problem with no 4. I put some oil in the bore and no4 went
straight up to 13 bar which suggests rings, although I may have put more oil
in than the teaspoon that Haynes recommends, could some of it found it's way
on to the valve seats ?.
Has anyone else had problems with no 4 cyl on a 1.8 20v engine.
Is lpg more prone to ring problems, I hadn't heard that. Any suggestions or
thoughts.

It looks like I either need to dig deep into my pockets or spend many hours
in the garage pulling the engine to bits.

Steve

W reg passat 1.8 20v with Necam lpg system.

No, I have 1.8T 2002 petrol Passat with 101,000 miles, no problems so far.
What's the mileage on yours ?
Out of interest, did you notice any difference between petrol and lpg (when
lpg was ok ) ?
Sukhi

"stevet" wrote in message
...
Hi All

I've been having a problem with a mis-fire while running on lpg for the
last couple of months. I have gradually changed all of the ignition
components, plugs, coil pack, leads etc. and still have the misfire. It
seems to run quite smoothly on petrol but misses on gas, more so at the
lower revs under load than at the higher revs.
So I decided to do a compression test today. (had to buy a new compression
tester as I couldn't find the old gunsons one from ages ago)
cyl #1 - 12 bar
cyl #2 - 11.5 bar
cyl #3 - 11 bar
cyl #4 - 7 bar
hmmm looks like a problem with no 4. I put some oil in the bore and no4
went straight up to 13 bar which suggests rings, although I may have put
more oil in than the teaspoon that Haynes recommends, could some of it
found it's way on to the valve seats ?.
Has anyone else had problems with no 4 cyl on a 1.8 20v engine.
Is lpg more prone to ring problems, I hadn't heard that. Any suggestions
or thoughts.

It looks like I either need to dig deep into my pockets or spend many
hours in the garage pulling the engine to bits.

Steve

W reg passat 1.8 20v with Necam lpg system.

Hi Sukhi
the car has 105,000 on the clock, when it was running well on lpg there was
no noticable difference between lpg and petrol. Maybe just slightly lumpy on
lpg for the first couple of minutes when the engine was stone cold. And when
you fill up on lpg the wallet doesn't take such a big dent.

Steve

"Sukhi" wrote in message
...
No, I have 1.8T 2002 petrol Passat with 101,000 miles, no problems so far.
What's the mileage on yours ?
Out of interest, did you notice any difference between petrol and lpg
(when lpg was ok ) ?
Sukhi

"stevet" wrote in message
...
Hi All

I've been having a problem with a mis-fire while running on lpg for the
last couple of months. I have gradually changed all of the ignition
components, plugs, coil pack, leads etc. and still have the misfire. It
seems to run quite smoothly on petrol but misses on gas, more so at the
lower revs under load than at the higher revs.
So I decided to do a compression test today. (had to buy a new
compression tester as I couldn't find the old gunsons one from ages ago)
cyl #1 - 12 bar
cyl #2 - 11.5 bar
cyl #3 - 11 bar
cyl #4 - 7 bar
hmmm looks like a problem with no 4. I put some oil in the bore and no4
went straight up to 13 bar which suggests rings, although I may have put
more oil in than the teaspoon that Haynes recommends, could some of it
found it's way on to the valve seats ?.
Has anyone else had problems with no 4 cyl on a 1.8 20v engine.
Is lpg more prone to ring problems, I hadn't heard that. Any suggestions
or thoughts.

It looks like I either need to dig deep into my pockets or spend many
hours in the garage pulling the engine to bits.

Steve

W reg passat 1.8 20v with Necam lpg system.