stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion

it is becoming difficult to start and when on petrol it
stutters........fine if i get it started but as soon as the thottle is
floored .......back firing and stutters (me thinks fuel starvation?)

on lpg its fine...........

or is it a fault on the petrol side........pump
...regulator...injectors?

pump works ........not pressure tested....tank cleaned out.

any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Backfire usually means spark issues to me....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Mick Miller wrote:
>
> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>
> it is becoming difficult to start and when on petrol it
> stutters........fine if i get it started but as soon as the thottle is
> floored .......back firing and stutters (me thinks fuel starvation?)
>
> on lpg its fine...........
>
> or is it a fault on the petrol side........pump
> ..regulator...injectors?
>
> pump works ........not pressure tested....tank cleaned out.
>
> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Backfire usually means spark issues to me....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Mick Miller wrote:
>
> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>
> it is becoming difficult to start and when on petrol it
> stutters........fine if i get it started but as soon as the thottle is
> floored .......back firing and stutters (me thinks fuel starvation?)
>
> on lpg its fine...........
>
> or is it a fault on the petrol side........pump
> ..regulator...injectors?
>
> pump works ........not pressure tested....tank cleaned out.
>
> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Backfire usually means spark issues to me....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Mick Miller wrote:
>
> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>
> it is becoming difficult to start and when on petrol it
> stutters........fine if i get it started but as soon as the thottle is
> floored .......back firing and stutters (me thinks fuel starvation?)
>
> on lpg its fine...........
>
> or is it a fault on the petrol side........pump
> ..regulator...injectors?
>
> pump works ........not pressure tested....tank cleaned out.
>
> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

wish it was.......it works fine on lpg so the spark side and timing is
fine........feels fuel starvation


>Backfire usually means spark issues to me....
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Mick Miller wrote:
>>
>> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>>
>> it is becoming difficult to start and when on petrol it
>> stutters........fine if i get it started but as soon as the thottle is
>> floored .......back firing and stutters (me thinks fuel starvation?)
>>
>> on lpg its fine...........
>>
>> or is it a fault on the petrol side........pump
>> ..regulator...injectors?
>>
>> pump works ........not pressure tested....tank cleaned out.
>>
>> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

wish it was.......it works fine on lpg so the spark side and timing is
fine........feels fuel starvation


>Backfire usually means spark issues to me....
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Mick Miller wrote:
>>
>> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>>
>> it is becoming difficult to start and when on petrol it
>> stutters........fine if i get it started but as soon as the thottle is
>> floored .......back firing and stutters (me thinks fuel starvation?)
>>
>> on lpg its fine...........
>>
>> or is it a fault on the petrol side........pump
>> ..regulator...injectors?
>>
>> pump works ........not pressure tested....tank cleaned out.
>>
>> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

wish it was.......it works fine on lpg so the spark side and timing is
fine........feels fuel starvation


>Backfire usually means spark issues to me....
>
>Mike
>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>88 Cherokee 235 BFG AT's
>
>Mick Miller wrote:
>>
>> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
>>
>> it is becoming difficult to start and when on petrol it
>> stutters........fine if i get it started but as soon as the thottle is
>> floored .......back firing and stutters (me thinks fuel starvation?)
>>
>> on lpg its fine...........
>>
>> or is it a fault on the petrol side........pump
>> ..regulator...injectors?
>>
>> pump works ........not pressure tested....tank cleaned out.
>>
>> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Do you live anywhere where it is cold enough to cause condensation to
freeze up?

I note the use of the word petrol, but just around freezing temps and
non or low use of the gas with less than a full tank in it can cause a
lot of condensation in the gas tank. This can plug up the pickup
sock/filter in the tank with ice beads.

Maybe try some gas line antifreeze?

Mike

Mick Miller wrote:
>
> wish it was.......it works fine on lpg so the spark side and timing is
> fine........feels fuel starvation
>
> >Backfire usually means spark issues to me....
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Mick Miller wrote:
> >>
> >> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
> >>
> >> it is becoming difficult to start and when on petrol it
> >> stutters........fine if i get it started but as soon as the thottle is
> >> floored .......back firing and stutters (me thinks fuel starvation?)
> >>
> >> on lpg its fine...........
> >>
> >> or is it a fault on the petrol side........pump
> >> ..regulator...injectors?
> >>
> >> pump works ........not pressure tested....tank cleaned out.
> >>
> >> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Do you live anywhere where it is cold enough to cause condensation to
freeze up?

I note the use of the word petrol, but just around freezing temps and
non or low use of the gas with less than a full tank in it can cause a
lot of condensation in the gas tank. This can plug up the pickup
sock/filter in the tank with ice beads.

Maybe try some gas line antifreeze?

Mike

Mick Miller wrote:
>
> wish it was.......it works fine on lpg so the spark side and timing is
> fine........feels fuel starvation
>
> >Backfire usually means spark issues to me....
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Mick Miller wrote:
> >>
> >> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
> >>
> >> it is becoming difficult to start and when on petrol it
> >> stutters........fine if i get it started but as soon as the thottle is
> >> floored .......back firing and stutters (me thinks fuel starvation?)
> >>
> >> on lpg its fine...........
> >>
> >> or is it a fault on the petrol side........pump
> >> ..regulator...injectors?
> >>
> >> pump works ........not pressure tested....tank cleaned out.
> >>
> >> any help.........thanks

Re: stutters and back fires when throttle floored ...wrangler 4.0 mpi
 

Do you live anywhere where it is cold enough to cause condensation to
freeze up?

I note the use of the word petrol, but just around freezing temps and
non or low use of the gas with less than a full tank in it can cause a
lot of condensation in the gas tank. This can plug up the pickup
sock/filter in the tank with ice beads.

Maybe try some gas line antifreeze?

Mike

Mick Miller wrote:
>
> wish it was.......it works fine on lpg so the spark side and timing is
> fine........feels fuel starvation
>
> >Backfire usually means spark issues to me....
> >
> >Mike
> >86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >88 Cherokee 235 BFG AT's
> >
> >Mick Miller wrote:
> >>
> >> I have a jeep wrangler 4.0 mpi ...with a LPG gas conversion
> >>
> >> it is becoming difficult to start and when on petrol it
> >> stutters........fine if i get it started but as soon as the thottle is
> >> floored .......back firing and stutters (me thinks fuel starvation?)
> >>
> >> on lpg its fine...........
> >>
> >> or is it a fault on the petrol side........pump
> >> ..regulator...injectors?
> >>
> >> pump works ........not pressure tested....tank cleaned out.
> >>
> >> any help.........thanks