ClubCJ - The CJ Lancer Club

went for a bit of a hoon just recently and when the engine got the tiniest bit hot, at about 5.5k rpm in 3rd or sometimes 4th gear power would cut out for a fraction of a second and then kick back in. Doesn't matter how hard I go in 1st or 2nd gear there is no problem but in 3rd and 4th the occasional sudden power cut out would occur. This problem has occurred shortly after having a motec m800 ecu installed and a dyno tune. The tuner beleives that he can't even start looking for the problem unless he gets the car out on a track to log data and I have no idea what to do. Has anyone had similar problems or does anyone have any idea on what I could do to try and fix the problem besides driving slow?

I would listen to your tuner and hit the track.

Or you could take it in to Mitsubishi lol see if they give you an excuse before or after they notice the motec.

do you have a boost gauge fitted, sounds a lot like overboost cut.

Sounds like a fuel cut to me and you shouldnt have to take it onto the track, if the tuner is anygood it can be done on the dyno, i mean he tuned it on the dyno didnt he??

Peanut wrote:Sounds like a fuel cut to me and you shouldnt have to take it onto the track, if the tuner is anygood it can be done on the dyno, i mean he tuned it on the dyno didnt he??

+1, Exactly, your tuner should be able to get a good enough idea what is happening without taking it on the track, obviously its 4th gear full throttle application and it is cutting fuel to protect the engine.

I have seen it many times before with high boost, normally dyno room are hot as it's hard to get the cool air in, when you take it out on the road and even more so at night when the air is cooler and more dense the boost will spike higher than what was tuned in the shop and the ECU will cut fuel to protect the engine.

Either way i think Peanut is right, and they should dyno it again to see what is going on, even if it doesn't do it, it should provide info about what it going on.

bad fuel pump relay ?

whitemonster wrote:bad fuel pump relay ?

i've noticed that there is a recall in the US for the fuel pump relay but MMAL hasn't issued one here. could be the problem

yeah and it's one of the major causes of engine blowing up in the US.

don't go WOT and have it checked , bad relay = no fuel = runs too lean = engine goes boom

might have a few bad ones in the MMAL batch

Why didn't the tuner get the logs of the motec and have a look.

They should be able to tell straight away if it is a boost issue etc etc.

Shouldn't even need the dyno.

I agree though it should be looked at, but looks to me like the tuner doesn't care too much.. I actually thought you were in Sydney for a minute there

arutha wrote:

whitemonster wrote:bad fuel pump relay ?

i've noticed that there is a recall in the US for the fuel pump relay but MMAL hasn't issued one here. could be the problem

I replaced the black one (there is one black one and one green one in our evo x's) in my car with the revised green one (we cant get the blue one here yet like the usa now have) just to be safe.

cost me a whole $10.50 and part number is 8627A011 (its listed as relay horn)

yeah , black one seems like the faulty one in USDM evo x , now they even have a blue one that cost lesser than the green one i think

whitemonster wrote:yeah , black one seems like the faulty one in USDM evo x , now they even have a blue one that cost lesser than the green one i think

Yeah but there new cheaper "blue" one is still more expensive than what the green one costs here (rrp for the green relay is around $15 here)

I think they were paying around $30 USD for the green relay.... which is the exact same part number and brand as the green one i just bought from my local mitsubishi dealer.

Having said that, the "old" black relay in my X showed no signs of problems on the dyno when we were doing a heap of runs back to back between the black and the green.

Sounds like a good thing to replace anyhow if we are going to tune our X's
For the sake of $15, might as well

fappy wrote:went for a bit of a hoon just recently and when the engine got the tiniest bit hot, at about 5.5k rpm in 3rd or sometimes 4th gear power would cut out for a fraction of a second and then kick back in. Doesn't matter how hard I go in 1st or 2nd gear there is no problem but in 3rd and 4th the occasional sudden power cut out would occur. This problem has occurred shortly after having a motec m800 ecu installed and a dyno tune. The tuner beleives that he can't even start looking for the problem unless he gets the car out on a track to log data and I have no idea what to do. Has anyone had similar problems or does anyone have any idea on what I could do to try and fix the problem besides driving slow?

You have a Motec M800 in a Ralliart Lancer? Weird, as the M800 doesn't work for either Ralliart Lancer or Evo SS-T.

Sure you have a Motec?

McCoy wrote:

fappy wrote:went for a bit of a hoon just recently and when the engine got the tiniest bit hot, at about 5.5k rpm in 3rd or sometimes 4th gear power would cut out for a fraction of a second and then kick back in. Doesn't matter how hard I go in 1st or 2nd gear there is no problem but in 3rd and 4th the occasional sudden power cut out would occur. This problem has occurred shortly after having a motec m800 ecu installed and a dyno tune. The tuner beleives that he can't even start looking for the problem unless he gets the car out on a track to log data and I have no idea what to do. Has anyone had similar problems or does anyone have any idea on what I could do to try and fix the problem besides driving slow?

You have a Motec M800 in a Ralliart Lancer? Weird, as the M800 doesn't work for either Ralliart Lancer or Evo SS-T.

Sure you have a Motec?

He has an Evo X 5 Speed Manual "GSR"