Engine missing at low rpm, any advice appreciated.
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Engine missing at low rpm, any advice appreciated.
Hi guys, the car seems to have developed a slight missfire, most noticeably between 1000-2000rpm. I've changed and gapped the plugs to 0.6mm and swapped over the MAF but to no avail. The Power FC's knock reading is jumping around too, mostly when i'm cruising or when the engine is cold. The car is also black smoking so obviously over fuelling. Its had new coil packs and injectors a year ago when the engine was rebuilt at API.
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make sure all the coil leads are not split as when i had my cossie it had the same problem and didnt find it until i reved the car when i was under the bonnet and seen a spark found it replaced the lead job done.hope this helps you taylor my boy.
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Ye it shows knock on start up, its a bit erratic bouncing up and down, and usually stays below a 1/3 of the way up the scale and only occasionally flashes the CEL at me, more so when i'm driving.
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if the cell light on the dash comes on thats peak and thats not good.give david a bell at api as you know hes a good guy and will point you in the right direction.sounds to me like something internal with the black smoke and knocking.i hope its not a big problem.apart from her missing what does she drive like.yea you can blame me mate your more than welcome.
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Lets hope its not that! I'm keeping my fingers crossed it's just a case of a simple missfire.
Shes pulling like a trooper and the knock reading all but disappears when she's on boost. The missfire and knock seems to be more prominent at low RPM and the car apart from slightly smoking drives fine.
Shes pulling like a trooper and the knock reading all but disappears when she's on boost. The missfire and knock seems to be more prominent at low RPM and the car apart from slightly smoking drives fine.
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No its not a lot of smoke, and it seems to get better when the engine warms up and is at higher revs, so wouldn't have thought it was the rings. The smoke is black so its unburnt fuel obviously caused by the missfire, so what i need to find out is what exactly is causing the missfire. I've changed the plugs and gapped them, so i'm thinking along the lines of Lambda sensor or maybe even a coilpack, even though they've only been in a year.
It needs to go to either Ace motorsport or Dave Coe in Swansea by the looks of it. Otherwise i'm just going to be buying parts that don't need replacing.
It needs to go to either Ace motorsport or Dave Coe in Swansea by the looks of it. Otherwise i'm just going to be buying parts that don't need replacing.
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Think i may have found the problem. First start up today since back from hols and she fired up first time, so i stuck my head under the bonnet to just give everything a quick visual check and noticed a bit of ehaust smoke coming up from under the engine. No obvious holes or blowing so i'm going to have to give it a proper check tomorrow, but that would explain the mixture being rich if there is a leak before the Lambda sensor...so fingers crossed this will be it.
That would also explain why the problem eases as the revs get higher, as the gases are flowing quicker so less are escaping through the leak.
That would also explain why the problem eases as the revs get higher, as the gases are flowing quicker so less are escaping through the leak.
Last edited by "Taylor"; 18 September 2008 at 05:44 PM.
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Hi mate ive got the same problem with mine, the fuel pump went down on her so had that changed but since then shes misfiring on low revs and when cruiseing but spot on when shes on boost, guys on the tech forum told me that it could be my coil pack shes booked in2 the garage now on monday so ill keep you posted
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yea you could check the headers, which ones have you got some of the aftermarket one's arnt that strong.we watched john big brakes expload at rrday at power station.that would prob be were id be looking.
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Got the original cast ones Daz. It wasn't what i thought though, the smoke i saw was coming from the catch can, so i assume condensation, it wasn't dense smoke more like exhaust type smoke. Its going to have to be plugged in, i'm all out of ideas.
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Ye, its been getting me down a bit Si, i know that theres a missfire but not whats causing it. Hopefully it'll just be one of the coilpacks, even though they aren't that old. Its booked in with Dave Coe in Swansea for Thursday, hopefully they can shed a bit of light on it.
Thanks for all the input Daz and everybody, hopefully it'll be nothing major. Heres an optimistic smile.
Thanks for all the input Daz and everybody, hopefully it'll be nothing major. Heres an optimistic smile.
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Did the moose tell you about my car problem, 2 days before i went away driving back from work suddenly lost all +boost preasure, it was running ok, ticking over & not smoking but felt like i had one of your trailers behind me, turned out to be the actuator has failed (thread in diaphram not holding the bar that goes to the waste gate), its ok tho Andy's on the case.
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Did the moose tell you about my car problem, 2 days before i went away driving back from work suddenly lost all +boost preasure, it was running ok, ticking over & not smoking but felt like i had one of your trailers behind me, turned out to be the actuator has failed (thread in diaphram not holding the bar that goes to the waste gate), its ok tho Andy's on the case.
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Ye he did say about it saturday, strange for the actuator to fail. I would have thought Andy would replace it for you, being that the turbo was brand new and is only a year old. Hope the hols were good? I had a wicked time on mine, first day back in work today...i could have killed that alarm clock!
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Fancy a swap? lol.
Bad news on the car today Dave Coe had a look at it for me and it turns out 1 of the pistons is knackered, how bad it is i won't find out until he strips it wednesday. When he turned the engine over it was puffing blue smoke out of the oil filler cap, so there wasn't compression in one of the cylinders. To say i'm gutted is an understatement, the engine was only rebuilt a year and a half ago at API. I'll have to wait and see what he finds before i decide what to do, there comes a point where you can't just keep ploughing money into it. ...is this the end of scooby ownership for me? I hope not as i've developed a strange bond with the old girl.
Bad news on the car today Dave Coe had a look at it for me and it turns out 1 of the pistons is knackered, how bad it is i won't find out until he strips it wednesday. When he turned the engine over it was puffing blue smoke out of the oil filler cap, so there wasn't compression in one of the cylinders. To say i'm gutted is an understatement, the engine was only rebuilt a year and a half ago at API. I'll have to wait and see what he finds before i decide what to do, there comes a point where you can't just keep ploughing money into it. ...is this the end of scooby ownership for me? I hope not as i've developed a strange bond with the old girl.
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Has dave mentioned his 2.5 conversion yet? He try's to sell me one everytime i walk in there I had the same feeling with mine the beginning of the year,it just seems like problem after problem
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Gutted for you mate, hope you get it sorted in expensively if possible mate, know how you feel mate, i've been there myself. Hang on in there mate, most will feel like you are now but there will be light at the end of the tunnel
simb
simb