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Discussion Starter · #1 ·
Hi, my 2007 TnT starts up fine & runs on 3 cylinders when cold, However
when I stop & turn it off, it runs on 2 cylinders for 1 to 3 minutes when
started again. Has anyone else experienced this problem. I have been told
it is a leaky injector, a bad spark igniter, a problem in the computer. Where
should I start? Any help would be much appreciated.
 

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I'm firing on three
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Bianc, which cylinder is out?....a common problem is the stick coils normally no 2 cylinder packs up (particularly if the bike has got wet at some time) my sport had no2 and 3 pack up after less than 1800 miles...the coils need to have a light coating of grease on them before re-fitting and make sure the top is totally sealed, so no moisture can enter between the coil and the cylinder head...Normally when a coil packs up its for good not intermittently.
so the first thing I would do is check all the plug in connections on the injectors…… unplug the connectors completely then put back on after spraying with a little WD40 and see how you go.
vtxbrit:)
 

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when I stop & turn it off, it runs on 2 cylinders for 1 to 3 minutes when started again. Has anyone else experienced this problem. I have been told it is a leaky injector, a bad spark igniter, a problem in the computer. Where should I start? Any help would be much appreciated.
Spark Plugs are cheap. Start there. One could be cracked.
 

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It is most likely going to be a coil stick problem. I had this problem with my 04 TNT. When you first start the bike from cold it will normally run fine as the idle is programmed to run higher for a few minutes until reaches running temperature, then the revs drop and this is where you then experience the bike running on two cylinders at idle. If you rev the engine it should cut back in. As in the previous thread when running on two cylinders, you should be able to tell which one is not working by the temperature of the downpipes.

The coil sticks are vertically slotted in place and have a rubber ring which seals the top of the hole they slot into. However this is not ideal as moisture can easily get past this and gets trapped in the slot with your coil stick which are very prone to rusting up and corrode very quickly. When they are fitted, a ring of silicone sealant should be applied around the top to make them weather/moisture proof. They're not cheap but fairly simple to refit, but after removing the old one, make sure you clean out the hole properly using compressed air etc before sealing in the new one. Will be worth checking the condition of the others and also sealing them into place.
Good luck!
 

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BIANC

As everyone says its likely to be a coil but you might just take the radiator filler cap off and check all is OK. I'm sure it will be fine but it wasn't on my 04!
 

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I think Pike means it could possibly be a headgasket failure!

Personally I believe that a coil stick has gone down, easy fix though I would blow out all the sparkplug recesses (before removing them) then clean the plugs up and then dry and clean the coil sticks, grease them up and seal both the inner and outer parts of the rubber seal with silicone. Should sort the problem!
 

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Hi, my 2007 TnT starts up fine & runs on 3 cylinders when cold, However
when I stop & turn it off, it runs on 2 cylinders for 1 to 3 minutes when
started again. Has anyone else experienced this problem. I have been told
it is a leaky injector, a bad spark igniter, a problem in the computer. Where
should I start? Any help would be much appreciated.
Need more details dude.... It runs okay when cold, does it continue to run okay when warm if you haven't turned it off?

It runs okay when cold.... do you turn the engine off while it is still cold or after it has warmed up?

Does it have the exact same problem everytime you go through this ritual?

I agree with vtxbrit, if it is a coil the problem will be there all the time. My guess is the excessively rich cold running mixture is fouling the plugs and they won't fire cleanly until the ECU has leaned out and the engine is warm enough to clean the plugs again.
 

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Hi Jonny o,I don't know much about engines really,but could you explain why if you have rich fuelling on start up,why would two cylinders run ok but not the third? As i said i don't know much but would like to glean knowledge off of others who do know, Cheers Russ:bow:
p.s if it is the coils i would buy new citroen/peugeot ones ,do the mods then fit ,you might do all the work taking out and cleaning the old ones for them not to work and have to do it all over again to fit new ones,i know because it happened to me a few months ago.Local citroen dealers do coils for around £29,but if you do a forum search for coils i'm sure i have seen a link for them for about £18 pounds each.The mods are very easy to do in minutes.
 

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why if you have rich fuelling on start up,why would two cylinders run ok but not the third?
Johnnyo last line basically describes it. My guess is the excessively rich cold running mixture is fouling the plugs and they won't fire cleanly until the ECU has leaned out and the engine is warm enough to clean the plugs again.
Electricity takes the path of least resistance. When a plug or even a coil is wet or damp the flow of electricity would follow the wet fuel and not spark(jump) across the electrode. If you have one plug that is slightly fouled and becomes wet on startup (rich mixture) it will not fire until the mixture is leaned off -burnt off -blown off or evaporated from the other cylinders heat buildup.. This can also happen to a coil that is either damp or has hairline cracks which then absorb moisture creating a better path for the electrons to flow.
I am not sure the type of plg in this engine but older style plugs need the correct gap. If the gap is too large and the plug gets wet it will again take path of least resistance. that is why we had clean and regap spark plugs. Too small a gap and we do not get the optimum spark.
Hope this helps.

Paul
 

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Discussion Starter · #11 ·
Now Running On 3 Again

Hi Guys, Just Wanted To Let You Know That The Problem I Had With My Bike Running On 2 Cylinders Sometimes, Turned Out To Be Water Entering The Seal Around The Top Of The Igniter, Shorting It Out At Low Revs. Thanks For The Help. Bianc
 
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