390SE one cylinder down on initial start up
Discussion
Hi all. So after almost a month of holiday it's back to work and back to the Wedges. Quick question but the 390SE now starts on the button. Today I've received a spare ECU and AFM which I've fitted. The ECU is a Tornado modified unit. Once the engine runs for a few minutes it runs clean, sounds fantastic and feels more responsive than with the old ECU/AFM, however with both set ups when the engine first fires up it runs on 7 cylinders and then after maybe a minute of running it clears and then runs on 8.
I'm suspecting either a leaking injector or a sticking tappet although there's no tappet noise, and all tappets are new. If it is the injector leaking then would it take up to a minute before it's fully charged and fueling okay? Given the high pressure pump I'd have thought it would prime and run within seconds?
When I changed the AFM I did notice the smell of petrol in the inlet pipe so coming from the plenum area. There are no external fuel leaks on the injectors or associated hoses so just wondering what it could be.
Any clues?
I'm suspecting either a leaking injector or a sticking tappet although there's no tappet noise, and all tappets are new. If it is the injector leaking then would it take up to a minute before it's fully charged and fueling okay? Given the high pressure pump I'd have thought it would prime and run within seconds?
When I changed the AFM I did notice the smell of petrol in the inlet pipe so coming from the plenum area. There are no external fuel leaks on the injectors or associated hoses so just wondering what it could be.
Any clues?
Hi Keith...Just check to make sure that all the plugs are firmly connected..When you start it have a feel with your finger up under the N/S of the plenum for any leaks on the fuel hoses/Rail...It also kind of sounds like there is a break in the injector wire and it may be expanding and making contact once the engine has warmed up..I guess the only way would be to test...Hope you find it...Ziga
PS: The smell may be coming from the 9th injector/Cold start
PS: The smell may be coming from the 9th injector/Cold start
With the engine running for a minute or so, the problem is cured, probably because the heat generated by the engine cures the problem. Therefore, if the heat helps, then it points to something electrical like a faulty spark plug or possibly a lead, hence the smell of unburnt fuel. Just a thought.
Tony. TCB.
Tony. TCB.
Thanks gents, it will be going on the rolling road soon to get set up properly but I'd rather try and find the fault before it gets a good thrashing. The laser temperature measurement doesn't work as Scott found out previously when he was originally fault finding. According to the temperatures on the manifold all was well even though cylinder 1 exhaust had no lobe whatsoever on the exhaust valve.
I'll start with plugs first (cause they're cheap!) and then try leads which I can swap off the 350i which I know are good. The injectors were all refurbished last year by Mr Injector shortly before I bought the car but I suppose that doesn't guarantee one could have failed or be leaking.
Given the new camshaft and tappets I'm hoping it's not related to that. I might give the engine a flush and replace oil and filter, just in case.
Once the engine has run for a minute then all is well so I'm assuming it's something simple. Fingers crossed.
I'll start with plugs first (cause they're cheap!) and then try leads which I can swap off the 350i which I know are good. The injectors were all refurbished last year by Mr Injector shortly before I bought the car but I suppose that doesn't guarantee one could have failed or be leaking.
Given the new camshaft and tappets I'm hoping it's not related to that. I might give the engine a flush and replace oil and filter, just in case.
Once the engine has run for a minute then all is well so I'm assuming it's something simple. Fingers crossed.
A little story, which is totally true.
Once upon a time, a long while ago ....
One of my mates rang me up asking for help, he had just done a rebuild (Cologne V6) and couldn't figure out why engine was missing a cylinder. He had checked injector was working, checked valves going up and down, the usual stuff.
I went to help and spotted that the relevant spark plug was completely closed up. He looked at me and said, "But I'm *sure* I checked it...."
Two secs with screwdriver and problem solved....
Just shows even the best of us screw up sometimes....
Once upon a time, a long while ago ....
One of my mates rang me up asking for help, he had just done a rebuild (Cologne V6) and couldn't figure out why engine was missing a cylinder. He had checked injector was working, checked valves going up and down, the usual stuff.
I went to help and spotted that the relevant spark plug was completely closed up. He looked at me and said, "But I'm *sure* I checked it...."
Two secs with screwdriver and problem solved....
Just shows even the best of us screw up sometimes....
Hi Keith...Do you have an adjustable FPR on the 390SE or is it a solid state type?...If its the aftermarket adjustable what is your fuel pressure set to?....Make sure the connection on the power resistor on the N/S inner wing is good...I hate to say it but a worst case scenario is the ECU plug...A wire maybe out of its seat..I would check the female plug as this issue is prevalent with both ECU's....
I would carefully pop off each injector plug and test the resistance and continuity of each...(Especially if i knew how to use a multi-meter)....
Then theres the test that you do with the flap of the AFM and injectors...Someone who is more familiar with this may be able to explain...(I will book mark it then).
I found some interesting info...Worth downloading it just for reference...Or maybe a visit to our old friend Ramon's site...
https://www.google.co.uk/url?sa=t&rct=j&q=...
Out of interest was the CTS new?
Cheers
Ziga
I would carefully pop off each injector plug and test the resistance and continuity of each...(Especially if i knew how to use a multi-meter)....
Then theres the test that you do with the flap of the AFM and injectors...Someone who is more familiar with this may be able to explain...(I will book mark it then).
I found some interesting info...Worth downloading it just for reference...Or maybe a visit to our old friend Ramon's site...
https://www.google.co.uk/url?sa=t&rct=j&q=...
Out of interest was the CTS new?
Cheers
Ziga
RCK974X said:
A little story, which is totally true.
Once upon a time, a long while ago ....
I read the story up until this point when I put the screen on hold and dashed into the kitchen to grab a cup of tea and some biscuits while I scrolled down to read the rest. Then I read you fixed it with a screw driver in a few seconds. To be honest I was disappointed, as I expecting a more dramatic story and a lot longer. I was expecting to hear things like you dismantling the engine on the roadside and then put it all back together only to find it was a spark plug fault, and then you started swearing etc etc. Still never mind. At least it cured the problem and your mate was happy.Once upon a time, a long while ago ....
Tony. TCB.
As we are talking RV8 here, I am allowed to comment.
I have had about 8 misfires, most of which were down to plug extenders. Several electrically dead, a couple that didn't clip on properly. I found which one with ten quid's worth of digital thermometer pointed at the exhaust manifold inthe first minute of running the engine. Even found a double misfire that way last time.
So if it was my RV8, I'd start with the thermometer. It will narrow down any problem with a plug, plug lead or extender to the cylinder concerned.
I have had about 8 misfires, most of which were down to plug extenders. Several electrically dead, a couple that didn't clip on properly. I found which one with ten quid's worth of digital thermometer pointed at the exhaust manifold inthe first minute of running the engine. Even found a double misfire that way last time.
So if it was my RV8, I'd start with the thermometer. It will narrow down any problem with a plug, plug lead or extender to the cylinder concerned.
ElvisWedgely said:
I read the story up until this point when I put the screen on hold and dashed into the kitchen to grab a cup of tea and some biscuits while I scrolled down to read the rest. Then I read you fixed it with a screw driver in a few seconds. To be honest I was disappointed, as I expecting a more dramatic story and a lot longer. I was expecting to hear things like you dismantling the engine on the roadside and then put it all back together only to find it was a spark plug fault, and then you started swearing etc etc. Still never mind. At least it cured the problem and your mate was happy.
Tony. TCB.
Hmmm....sorry about that, but it's what happened. Here's some other quick ones.Tony. TCB.
I did re-assemble my first Triumph L6 engine with the main bearing caps on backwards (Ford 1600s had the indents on opposite sides, Triumphs did not) and then had to disassemble the entire bottom end again. Engine wouldn't turn over on starter.
Rebuilding an engine and pouring some gas down the carb to get it going, only to have it backfire and blow gas back out all over someone's face, who then was screaming how it burns your eyes (proper leaded gas too). We laughed, but he didn't.
I drove home without a clutch (clutch fork/lever broke) across town in Stockport about 10 miles through traffic....
I still have the scar on my hand when the lifting eye on the engine hoist broke, and I didn't quite get my hand out of the way fast enough.
Sump survived too - bent but didn't burst.
Making it home after the rear diff on my Marlin kit car exploded (well not quite, but big hole in the case - GT6/spitfire diff ) and I crawled along to truly horrible noises to a friend's house about 5 miles away at 10mph...
Perhaps we should start a thread "Funny but true disaster stories" ??
Right, I started the engine and pulled the HT leads while it was running on 7 cylinders and it's number 4 that's missing but only for that first minute. I've changed the plugs and the HT lead but it made no difference. So I'm guessing it's injector or a lazy tappet not pumping up? Given the heavy sludge that was in the engine when it was stripped for the new camshaft I'm suspicious that the tappet oil way may have crap in it.
I've got a can of Wynnes engine flush but having had a read through numerous posts there is some concern in using engine flush.
Any advice? The engine is running Morris Classic Golden Film 20w/50. Would a thinner oil be preferable given the supposed state of tune from the John Eales engine?
I did have a spin around the block and with the Tornado modified ECU and pukka 390SE AFM off Paul it just goes and pulls like stink without any hesitation. On the very damp roads it did squirm a little though every time the load pedal was applied. cant wait to get it on the RR.
I've got a can of Wynnes engine flush but having had a read through numerous posts there is some concern in using engine flush.
Any advice? The engine is running Morris Classic Golden Film 20w/50. Would a thinner oil be preferable given the supposed state of tune from the John Eales engine?
I did have a spin around the block and with the Tornado modified ECU and pukka 390SE AFM off Paul it just goes and pulls like stink without any hesitation. On the very damp roads it did squirm a little though every time the load pedal was applied. cant wait to get it on the RR.
Am I correct to assume you don't have a plug extender on plug 4?
If you do, try starting without it.
If you don't, try damp start or WD40 to remove the moisture.
In this winter weather my car (V8 Developments 5 litre Chimaera) regularly starts on somewhere between 5 and 8 cylinders, but it clears in the first mile or so.
I just put it down to moisture in the electrics.
If you do, try starting without it.
If you don't, try damp start or WD40 to remove the moisture.
In this winter weather my car (V8 Developments 5 litre Chimaera) regularly starts on somewhere between 5 and 8 cylinders, but it clears in the first mile or so.
I just put it down to moisture in the electrics.
adam quantrill said:
Don't forget the dizzy cap before pulling off more complicated engine parts - in case there's a fault on that plug lead.
Right, done the dizzy cap, done the leads, done the spark plugs, done WD40 over everything and still the same minute or so running on 7 cylinders from cold. If the engine sits for 10 minutes after running then no misfire. I'm still suspecting one of the tappets is slow pumping up.Again is the 20w/50 I'm using maybe too thick? I'm assuming that thinner oil will get around quicker. Steve Heath recommends Mobil 1 synthetic. Are more modern oils likely to gradually remove old deposits?
What are others running their 390's and 400's etc on?
Thanks.
I am doing a lot of track days with my RV8 engine, so use Shell Helix Racing 10w60, to give protection from the extremes of heat on track (any time other than winter, the car runs at 90 degrees and over the entire time I am on track) as well as make the oil suitable for winter cold starts. The engine is now 25,000 miles old and I am not aware of any issues, but ask any Chimaera/Griffith forum and you will get about 20 different answers.....
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