Jamie.Frost Posted May 24, 2018 Author Share Posted May 24, 2018 38 minutes ago, Ben (bunje) said: Can't remember. Someone had a blue fiesta with an St engine in it with omex managment he couldn't get it to start after pretty much doing nothing to it. Just wondering if it was your car. No wasn’t me buddy Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 26, 2018 Author Share Posted May 26, 2018 Hiya, I haven't managed to get down there with a laptop to get any screenshots of the Omex yet but found something very interesting last night, I've basically diagnosed it as a huge misfire at low revs. I put a timing light on cylinders 1 & 2's HT leads to get a 'spark reading' and it was showing an intermittent flash, the timing light would be consistent and then all of a sudden would stop, then when it started again, that's when the bodies would backfire and shoot a flame - in my eyes, there would still be fuel being dumped into that cylinder as the spark plug lost it's power and then made a huge bang as it started sparking again do to the extra fuel in the cylinder thus shooting a flame through the inlet valves - whats peoples thoughts on that? I also managed to check continuity from bank 1 & 2 off the coilpack going to the omex pins and they were perfect, I'm also getting a constant 11v at the coilpack live whilst cranking. I might take my Omex unit up to them (Omex) this week so i can get it checked, as I know with zetec's and duratec's that if the coilpack starts to breakdown they can spike the ignition control part of the ECU, What are peoples thoughts on this? Thanks in advance Quote Link to comment Share on other sites More sharing options...
Kit Car Electronics Posted May 26, 2018 Share Posted May 26, 2018 Disconnect and reconnect the crank sensor connector, and give it a good wiggle at idle- it sounds like you're looking for a pretty gross fault like total loss of sync at low speed (the sensor output is small at low speed so often more likely to give errors there). Mechanically, also check that the cam timing hasn't slipped massively (eg when you started the engine before the problems). Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 26, 2018 Author Share Posted May 26, 2018 2 minutes ago, Kit Car Electronics said: Disconnect and reconnect the crank sensor connector, and give it a good wiggle at idle- it sounds like you're looking for a pretty gross fault like total loss of sync at low speed (the sensor output is small at low speed so often more likely to give errors there). Mechanically, also check that the cam timing hasn't slipped massively (eg when you started the engine before the problems). Thanks for your reply, I'll do that, funny you should mention crank sensor though as I noticed yesterday that the crimp that fits onto the crank shaft sensor plug on the omex loom looks like its been crushed at some point but unsure how to re do it - I'll deffo give it a wiggle at idle when running and see what it does, I've checked the cam timing and its all spot on, crank pulley hasn't slipped either. I suppose if I'm getting a dodgy crank sensor reading then it would be throwing ignition timing all over the shop wouldn't it? Quote Link to comment Share on other sites More sharing options...
Kit Car Electronics Posted May 26, 2018 Share Posted May 26, 2018 1 minute ago, Jamie.Frost said: Thanks for your reply, I'll do that, funny you should mention crank sensor though as I noticed yesterday that the crimp that fits onto the crank shaft sensor plug on the omex loom looks like its been crushed at some point but unsure how to re do it - I'll deffo give it a wiggle at idle when running and see what it does, I've checked the cam timing and its all spot on, crank pulley hasn't slipped either. I suppose if I'm getting a dodgy crank sensor reading then it would be throwing ignition timing all over the shop wouldn't it? Yes Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 26, 2018 Author Share Posted May 26, 2018 4 minutes ago, Kit Car Electronics said: Yes Okay thank you, any idea on how to sort out the crushed connector that fits onto the Omex loom? I suppose if it's crushed that badly then it could cause problems with low voltage signals couldn't it and would explain also why the misfire disappears at higher revs as the signal would be higher - am I on the right lines? Lol, Thanks Quote Link to comment Share on other sites More sharing options...
Kit Car Electronics Posted May 26, 2018 Share Posted May 26, 2018 If that connector is the problem, they're quite widely available so worth replacing if damaged. Eg Here - you just need a crimp tool to fold the cable grips over (and a little patience to get it right). Make a note of the wire colours as the signal polarity matters. Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 26, 2018 Author Share Posted May 26, 2018 5 minutes ago, Kit Car Electronics said: If that connector is the problem, they're quite widely available so worth replacing if damaged. Eg Here - you just need a crimp tool to fold the cable grips over (and a little patience to get it right). Make a note of the wire colours as the signal polarity matters. Brilliant, thanks for your help! Don't understand why it would happen/not decide to work overnight with the battery disconnected but there we go - i suppose that's electrics for you lol. Quote Link to comment Share on other sites More sharing options...
Kit Car Electronics Posted May 26, 2018 Share Posted May 26, 2018 Well hopefully it's nothing more serious- the wiggle test is normally a good one, anyway- fingers crossed for you. Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 26, 2018 Author Share Posted May 26, 2018 13 minutes ago, Kit Car Electronics said: Well hopefully it's nothing more serious- the wiggle test is normally a good one, anyway- fingers crossed for you. Okay, thank you Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 27, 2018 Author Share Posted May 27, 2018 20 hours ago, Kit Car Electronics said: Well hopefully it's nothing more serious- the wiggle test is normally a good one, anyway- fingers crossed for you. Hiya mate, been down my unit to look at the crankshaft sensor wiring and after a lot of meddling I found that the blue cable was broken, I thought oh my god, I’ve found the problem... soldered and heatshrank it all back together, connected all back up and made no difference, all I was confused about though was there are two wires going to the crank plug and there’s one in the middle without any sheathing on - literally a bare wire... does it need to go anywhere do you know as I’ve only got two connected up currently (the red and blue)... cheers buddy Quote Link to comment Share on other sites More sharing options...
Kit Car Electronics Posted May 27, 2018 Share Posted May 27, 2018 I think a photo would help. I suspect the bare wire is probably just the shield, you should find it connected to the omex ground (check with a multimeter). It seems a rather large coincidence that the blue wire was broken, maybe it is still fractured inside the wire. Is it a new loom or a used one? Also check that the red and blue wires are connected to the correct pins on the Omex for the correct signal polarity. Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 30, 2018 Author Share Posted May 30, 2018 Hello again!! I've been on the phone to Guy at Omex this morning and he’s diagnosed my problem as a major air leak (ties in with my lack of brake pedal problem) - he diagnosed it by doubling the fuelling going through the injectors and the idle rose to 5K and he said that will definitely be an air leak. I've fitted a new inlet manifold gasket as well as checking the connections for the servo pick-up going to the servo - does anybody know where else I could be leaking air from? I’ve also got an evap/purge valve that isn’t connected up - could this be causing an issue? Thanks in advance, Jamie Quote Link to comment Share on other sites More sharing options...
Jamie.Frost Posted May 30, 2018 Author Share Posted May 30, 2018 On 27/05/2018 at 21:48, Kit Car Electronics said: I think a photo would help. I suspect the bare wire is probably just the shield, you should find it connected to the omex ground (check with a multimeter). It seems a rather large coincidence that the blue wire was broken, maybe it is still fractured inside the wire. Is it a new loom or a used one? Also check that the red and blue wires are connected to the correct pins on the Omex for the correct signal polarity. Hiya mate, Omex didn’t really seem concerned about the problem I had with the crank sensor because i’ve joined it back up...? They’ve diagnosed it as an air leak? (See above post) Quote Link to comment Share on other sites More sharing options...
Nick Mace Posted May 30, 2018 Share Posted May 30, 2018 Do you have the standard ford intake? In a westfield set up the vacuum hoses aren't used and a number of the hose connectors are blocked off with silicone/rubber caps. I had a cap fall off (may have been a backfire which popped it off) and it wouldn't run at all well. You should check that all of the vacuum hoses are on properly, not split etc. I'm not sure what the purge valve is, but if not using it means there is a source of air for the intake which shouldn't be there, then I would say that it should be blocked off. Quote Link to comment Share on other sites More sharing options...
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