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+--- Thread: Poor engine performance (/showthread.php?tid=6282)
Poor engine performance - Hardrinseron - 06 Mar 2022
Hi all,
My car starts first time and ticks over bang on 750rpm. At idle it sounds fine but as soon as you give it a bit of gas it starts popping occasionally. In addition to this power is well down and tops out at around 50mph.
Has anyone seen this before? Can anyone suggest a cure? I think it could be the injectors that are clogged up but it would be good to know someone has seen the same
Thanks!
Darren
RE: Poor engine performance - Rissy - 07 Mar 2022
A process of possible reason eliminations to be carried out i'd say.
When you say the power tops out at around 50mph, what happens at that point? Any bunny hopping or jittering or anything else?
RE: Poor engine performance - Hardrinseron - 07 Mar 2022
(07 Mar 2022, 09:48)Rissy Wrote: A process of possible reason eliminations to be carried out i'd say.
When you say the power tops out at around 50mph, what happens at that point? Any bunny hopping or jittering or anything else?
thanks for the reply. No it just seems to hit a flat spot where the power tops out. Like i said though it pops frequently even from setting off so its not running smoothly
RE: Poor engine performance - Rissy - 07 Mar 2022
I'd start be checking and possibly replacing injectors (all equal and good spray pattern and decent volume against time), spark plugs, inline fuel filter (this one has proven to give me issues in the past). Do a fuel flow check of the fuel pump (at the tank return) - you want from memory around 850ml in 30 seconds. If you're not meeting minimum flow, you'll probably want to also check the in-tank fuel filter and think about replacing the pump.
The other things to check is the warm up curve fuel pressure and the primary fuel pressure. Values can be found in the workshop manual, but remember, if you're running a modern free flow exhaust system, you'll need a stronger primary fuel pressure than stated in the manual.
RE: Poor engine performance - Hardrinseron - 07 Mar 2022
(07 Mar 2022, 10:04)Rissy Wrote: I'd start be checking and possibly replacing injectors (all equal and good spray pattern and decent volume against time), spark plugs, inline fuel filter (this one has proven to give me issues in the past). Do a fuel flow check of the fuel pump (at the tank return) - you want from memory around 850ml in 30 seconds. If you're not meeting minimum flow, you'll probably want to also check the in-tank fuel filter and think about replacing the pump.
The other things to check is the warm up curve fuel pressure and the primary fuel pressure. Values can be found in the workshop manual, but remember, if you're running a modern free flow exhaust system, you'll need a stronger primary fuel pressure than stated in the manual.
Thanks, i've got new fuel filter, plugs and fuel lines, and my tank was cleaned out completely just before xmas. I've start with the injectors and work back from there. Thanks!
RE: Poor engine performance - Chris Williams - 07 Mar 2022
All good advise from Chris (above) as always. I would start by checking the injectors as suggested. There's a great way just by using jam-jars. I would do that test (google) and report back from that.
Chris