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Old 17th August 2020, 19:43   #51
mbonwick
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I'm using a pscan tool to read the codes. Interesting that it lists P1300 differently to RAVE, but that's irrelevant really as it still doesn't help give any direction!


For now, reverting back to completely standard (bearing in mind all we're dealing with is porting/VVC manifold) is out of the picture - it's just too much work while still needing the car as a daily 5+ days of the week.


Interestingly one of the mechanics commented when it was in for MOT (which it passed by the way with flying colours on the emissions!) that at idle it sounded/felt like a fuel delivery issue, so I'll definitely be looking to explore that when I get chance - I know you've mentioned it before Simon, I just haven't yet had chance.
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Old 21st August 2020, 10:01   #52
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I've mentioned this a couple of times but seeing as you haven't made much progress, worth mentioning it again. You can buy a Colourtune plug for about thirty quid, and then you can see directly into each cylinder and whether you are getting a consistant spark, running rich, running as it should or running too lean.


Very helpful for pointing you in the right direction.


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Old 21st December 2020, 22:03   #53
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Right, digging this one back out as I know people like updates.

Unfortunately I still haven't solved the running issue, but I have fixed the reluctant starting by replacing the fuel filter.
Decided to take the tank completely off while it was in the garage for the tank straps to be replaced, opened up the filter housing and boy was it choked up! I know the filters go black, but you shouldn't be able to scrape the gunge off them with your finger!!




That improved the running in general for a couple of days - it wasn't perfect but I figured it would settle as the fuel trims readjusted. Sadly that hasn't been the case and its gone back pretty much to how it was. It has crossed my mind that I may have a weak/failing fuel pump - perhaps the excessive black gunk is the insides wearing out (I know that's pretty much unheard of, but this car seems to love coming up with new, never before seen problems - like the auto 'box sump rusting through!).
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Old 21st December 2020, 23:39   #54
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Quote:
Originally Posted by mbonwick View Post
It has crossed my mind that I may have a weak/failing fuel pump ...
I doubt it Michael. The fuel pumps on petrol engined cars are extremely reliable.

I've just looked back at earlier posts and you have fault codes for misfiring. I mentioned coil packs around that time which can cause this. How about a T4 session to find out which cylinders are affected?

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Old 22nd December 2020, 00:11   #55
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I've just looked back at earlier posts and you have fault codes for misfiring. I mentioned coil packs around that time which can cause this. How about a T4 session to find out which cylinders are affected?

Simon
Codes are for cylinders 2 and 4, so to me that rules out a failing coil pack. It was interesting though that last time it was on livedata the misfire counts for 2/4 were going through the roof but 1/3 remained at 0 - not sure I believe they were completely unaffected to be honest.
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Old 22nd December 2020, 21:33   #56
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Re the misfire, it might be worth looking closely at the wiring in the area underneath the throttle body and multi connector. It can chafe leaving bare wires exposed and the wiring for the coil packs is among the wires in that area and can be affected. Re the cold running problem, if it has a standard stat as opposed to a PRT it might be worth checking it to see if it has been drilled. The stat which came with my Rover 25 had two holes drilled in it both of which were about the diameter of a six-inch nail. It rendered the stat useless and it may as well have not been fitted at all. It caused running problems and overfuelling, the engine never got up to temp and the heater did not work as a result making the car cold and dangerous to drive in the colder months. Might be worth testing the stat if it shows no sign of having been tampered with.
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Old 2nd May 2021, 11:03   #57
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Mbonwick, just a quick question, when you start the engine from cold, does it misfire straight away ? Or after 20 or so seconds ?

Pete.
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Old 2nd May 2021, 11:11   #58
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I ask because I have a ZR and TF with the same problems. The TF is slightly worse. It starts fine, then after 20 or so seconds starts to chug, you can hear it from the exhaust, it will stall at junctions and doesn’t like restarting. But drives fine once up to temperature.
The ZR misfires under load under 2500 rpm, but not straight away, after a couple of minutes, then when the engine is hot, it’s fine.
I have a T4 and nearly everything has been changed, to no avail.

I’m starting to wonder if it’s a sticking valve that expands after a couple of minutes, causes the misfire, then when the whole engine is hot, stops sticking, or an injector problem. We have ethanol fuel here in France.

Pete.
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Old 2nd May 2021, 12:46   #59
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Initially, it would be perfectly fine then start getting worse after 20secs or so. Over the past year though it's morphed into a slight misfire at initial start that then gets worse. There seems to be less "flare" now as the engine catches - used to easily get over 1500rpm as everything fired for the first time, now its somewhere around 1250rpm usually.

It's so inconsistent with how severe the miss gets (and if the car stalls), but seems to be slightly better when there's more than 1/2 a tank of fuel. I am beginning to wonder if it's a fuel pressure/injection problem too
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Old 25th March 2024, 14:45   #60
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Hi,

did you ever get to the bottom of this problem ?

Pete.
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