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peter thomson
08-08-2007, 01:24 PM
Hi I have just fitted a boost controller a couple of weeks ago which I am still setting up now but I now seem to have a bit of a misfire and definite loss of power in 3rd gear and above.
It is not a really noticable misfire but almost a pulsing. Bit difficult to describe really.
I took out the front plugs and they were all set to 1.1mm and the centre plug was loose which I hope probably explains the problems and that increasing the boost has shown up these faults. I'm taking off the inlet manfold just now to check the rest and I've ordered a new set of plugs:
What do you guys think

Paul Beazer
08-08-2007, 01:35 PM
fuel cut?

Nutter_John
08-08-2007, 01:58 PM
I would say that your plugs could be blowing out , try a colder range

peter thomson
08-08-2007, 02:02 PM
It dosn't feel like fuel cut going by what others have said and I have ordered the plugs Kieran mentioned in another post for running higher boost. Thanks

Kieran
08-08-2007, 02:18 PM
Yeah, sounds like the cylinder pressure is fluffing out the spark kernel. 1.1mm is too big a gap, however it's a common mistake.... When you go to your local parts factor and say "it's a Galant VR-4", they look up VR-4 and almost always get the reference for the 3000GT... As it's also known as the "VR-4" in the US.

It's not too bad as the plug code is identical (Standard fit on both is NGK PFR6J), but the 3000GT has a bigger gap. Might be worth closing up the gaps whilst you wait for some new plugs.:scholar:

peter thomson
08-08-2007, 04:08 PM
Hi yes closed up the gaps as the rear ones were the same and I had oil in the centre rear sparkplug hole so I will change the rocker cover gaskets at the same time and replace my noisy lash adjusters. I'll see if closing the gap has improved things now. thanks

Kieran
08-08-2007, 04:10 PM
Hi yes closed up the gaps as the rear ones were the same and I had oil in the centre rear sparkplug hole so I will change the rocker cover gaskets at the same time and replace my noisy lash adjusters. I'll see if closing the gap has improved things now. thanks

Make sure you replace the inner gaskets around the spark plug holes too - order a rocker cover gasket and you'll just get the outer one. It's the spark plug hole gaskets that fail and let oil dribble into the spark plug holes - the heat from the rear turbo cooks them over time, you see.:scholar:

peter thomson
08-08-2007, 06:54 PM
Make sure you replace the inner gaskets around the spark plug holes too - order a rocker cover gasket and you'll just get the outer one. It's the spark plug hole gaskets that fail and let oil dribble into the spark plug holes - the heat from the rear turbo cooks them over time, you see.:scholar:

Thanks Kieran I had forgotten that.

Took it for a quick run to see if it felt better and it is responding better off the line, it did feel as if it was bogging down a bit before. I didn't push too hard though until the new plugs arrive.

On another point i have the boost controller running at 0.8 bar but it is spiking to 0.9. Is this too much as I do not seem to be able to improve on this.

Kieran
08-08-2007, 08:04 PM
Yeah, some members have set boost to 0.9 constant with standard fuelling, so a spike to that is probably not doing any major harm. If you want to be double sure, then the datalogger cable and evoscan will provide a good reference table if you want to make sure Knock stays at a safe level.

Oh, and take a chair when you go to your local $tealership for some plug hole gaskets.... £15 to you sir!!/Grrr

peter thomson
08-08-2007, 08:14 PM
Yeah, some members have set boost to 0.9 constant with standard fuelling, so a spike to that is probably not doing any major harm. If you want to be double sure, then the datalogger cable and evoscan will provide a good reference table if you want to make sure Knock stays at a safe level.

Oh, and take a chair when you go to your local $tealership for some plug hole gaskets.... £15 to you sir!!/Grrr

Hi I hope that is for 6 and not just one.

If I increase to 0.9 or 1 bar would a 0.1 bar spike be too much.

I'm going to fit a knocklink soon as well and an LC1 or LM1 depending on funds.

I don't have a laptop just now so the evoscan is out at the mo.

Kieran
08-08-2007, 08:20 PM
1 Bar of boost is possible and people have done this, but yes, I think you're wise to get an Air/Fuel monitor and a knock link. I would wait untill you've got this setup and then you can push further.

One further thought, unless your intake and exhaust has been sorted to be very free flowing, 1 bar is about all the turbos can cope with - they just can't hold much more beyond this without opening up the intake and exhaust.

peter thomson
08-08-2007, 08:25 PM
I have an Apexi cat back system and decat with an ARC box at the moment so they should be fine. Just have to sort out a cold air feed to the filter and probably a larger intercooler. I've still to get my SAFC set up as well but was going to wait until I was happy with the boost and I had finished fitting all the bits

peter thomson
08-08-2007, 11:58 PM
Oh, and take a chair when you go to your local $tealership for some plug hole gaskets.... £15 to you sir!!/Grrr

OK the price is for 1 seal/Grrr .What do they look like. Are they just rubber O rings or is there more to them than that. If they are just O rings does anybody know the size before I take off the rocker covers

peter thomson
17-08-2007, 11:20 PM
I fitted new plugs and leads tonight and I'll see if this has sorted the misfire tomorrow. If not I'll order a couple of new coils.
I picked up a couple of new coils for an FTO for 99p on ebay this week but unfortunatly they are different so back to ebay with them

peter thomson
18-08-2007, 12:40 PM
Ok tried the car today but there is no improvement. Do you think this could be the one or more coils starting to fail or something else. I may remove the boost controller to see if there is a problem with the solenoid.
It just does not seem to rev properly in 3rd and above from about 5000rpm and you can feel it is holding back but it is not a hard misfire if that is what is causing the problem.
Any chance it could be fueling?

Gly
18-08-2007, 10:10 PM
could be, you were having issues with the TRE fuel pump + FPR

have you tried the original mitsi parts?

peter thomson
18-08-2007, 10:27 PM
could be, you were having issues with the TRE fuel pump + FPR

have you tried the original mitsi parts?

Yes I am going to try refitting them tomorrow after I have tried swapping the coils. It is missing in all gears. Just not so noticable in 1st and 2nd. I removed the boost controller which did not help apart from making it less noticable.

peter thomson
19-08-2007, 12:34 PM
Ok measured the coil resistance this morning.
HT values on all 3 coils measure between 17.07 and 17.45k ohms
On the low tension side measuring between the top 2 pins I get 544 to 547ohms
But measuring between the top and bottom pin and the centre and bottom pin which I think is the earth I get no reading but on the 3rd coil i get a value 1.365M ohms between pins 1 and3 and 2 and 3 .I hope this means that there is a fault with this coil.
What do you think

peter thomson
19-08-2007, 04:04 PM
Fitted one of the new FTO coils I picked up on ebay but did not seem to make any improvement.
Refitted the boost controller and that confirmed it was not the coil as the misfire was worse
Removed the TRE pump and refitted the standard one.
Wow . Huge improvement.No misfire and so much quicker.
I was sure it would be the coil but no the pump was the problem.
Thanks for all the suggestions. At least I know it has the right plugs fitted now .

Kieran
19-08-2007, 05:09 PM
Glad you solved it. Not heard of a TRE pump giving up before, but still - glad it's fixed!:scholar:

bradc
21-08-2007, 09:55 AM
so how old was the tre pump?

peter thomson
21-08-2007, 10:27 AM
It was on the car for less than 2 months Brad but I bought it from Ghanda who had never fitted it. I think if I had not fitted the boost contoller I might not have realised there was a problem and that I would shortly have had a dead engine but I'll be fitting a LC1 shortly or the PLX gauge mentioned in another post.
What I did notice when the pump came out is that the matal collar on the outlet of the pump had come off.It may be that it had partially blocked the outlet.
The car starts first turn of the key now which it would not do when the TRE was fitted