I have a PPP + decat downpipe fitted to my MY00 Classic. The car has displayed some odd symptoms recently.

The idle has been rough to the point where the car rocked when at idlem although the revs have held steady. This came and went a couple of times and has now been replaced by a holding back when full throttle is applied, as the revs rise the car starts to go then struggles slightly all the way to the redline although light throttle driving is smooth. This second problem only seems to have started since I filled up with fuel a couple of days ago. As we don't have V-power or Tesco 99 up here I have the choice of ESSO or BP ultimate. The last 3 months I have been using ESSO.

What could the problem be: Lamda, MAF or simply the fuel?

Any help would be appreciated.

Thanks

 

When was the last time the plugs were changed?

Mine hesitated on full but was fine if applied slowly to full. Changed plugs, all fine.

I was also tempted to think maybe the leads and/or coil pack might be on the way out.

 

It has always been serviced by Subaru, don't know if the plugs were changed. I'll find out.

 

One reply, thats disappointing, never mind maybe more information on the symptoms will help.

Had a bit of a play with it tonight and I've narrowed down what seems to be happening. I searched the forum and tried a couple of thing before coming back on here.

Firstly I removed the boost solenoid and pipe work and cleaned it out including the standard restrictor (1.2mm). I then did an ecu reset, this showed no fault codes. I then went out on the road.

Once up to speed the hesitation started almost immediately, after several runs in different gears it was apparent that the higher the gear the more noticeable the hesitation.

With the car cruising in fifth I tried applying the throttle gently and then stamping down, no difference.

Still in 5th at 2200 revs I put my foot down, the car began to accelerate with plenty of urge, then at 2800-3000rpm it began to judder and hesitate, the acceleration continued at a much slower rate. At 3300 the juddering reached its peak then began to tale off a little and became a little smoother although hesitating all the time.

It feels like an ignition problem although I could be barking up the wrong tree.

Again thanks in advance.

Stephen

 

could be maf issues

 

If its missing on tick over have you tried disconnecting each HT lead in turn while its running? if one is pulled off and it still runs the same it must be a spark issue, if all ht leads make no difference more likely to be timing / fueling issue?

Dave

 

Just a thought have you checked all the pipework, boos hoses etc it could be overboosting, it sounds like it's when the boost is building up and it's not quite making it to full boost!
Have a look at the hoses first (sometimes the most obvious are overlooked)

 

I cured this changing plugs and 1 coilpack that had split and cleaning out boost solenoid!