So I own a 2001 JDM Spec Evo 7 currently experiencing some major issues. These issues has only recently occurred within the last week. No mods or changes were made recently. Problem occurred from out of the blue.

The car starts fine and drives fine for the first 10+ minutes until whatever is causing the issue, kicks in. I have noticed the issue only occurs when the car is hot. so if i was to cruise, the issue would take roughly 20 minutes to kick in, do some boosting and you will see the issue in 10 minutes. My Evo will randomly lose all power, not electricity but power in revs. I could put my foot flat in every gear and the revs wouldn't move up a mm, just revs drop to idle and car loses speed until she comes to a full stop then stalls. Once the issue has occurred, the car will start every time no issue but once it starts, she stalls straight away. wait 5 minutes or so, give her some gas as you crank it, she starts and has enough juice to drive for the next 5 minutes hoping home is within reach. Extra- today after changing the crankshaft sensor, test drove and issue occurred, was idling on the side of the road and the car fully turned off. it turned off really smooth that mates in the car thought i turned the key to turn the car off. really confused as i don't really understand what has enough power to turn the car off like that. The car is also misfiring when re applying gas, stalls when coming to a halt and engaging clutch going into neutral and check engine light flashes sometimes, majority of the time is WOT in 3rd or 4th.

PLEASE if anyone has any idea what the issue could be, don't be shy to post. i really need peoples opinion on what the issue could be. The car idles and drives fine until the issue occurs, and i believe it is getting the fuel and air it needs as afr reads fine and she drives and idles fine when cold.

I have done a compression test, all 4 came out mint and healthy. I have tried changing my cop with new coils and plugs, changed Cam angle sensor, had the TPS checked, double checked for boost leaks and just recently purchased and changed the Crankshaft sensor with a new one. None of these components improved the issue. It seems to be getting worse and worse (kicking in earlier and harder to start after the issue has occurred).

My next ideas were to change the fuel relay or intake air temp sensor. But any ideas that could be causing my issue and where to look next would be great. Please help!!

 

Map sensor? I just replaced my 4 bar but I'm on sd. Kind of similar to my symtoms but you seem more consistent. I think your stock jdm evo has map sensor too. It will cut off fuel if it doesn't read correctly. Specially when you boost.

 

Get a cheap fuel pressure monitor. Your fuel pump could be failing.

 

I have a OMNI power bar 4 map sensor already with my SD, have had it in the car for under a year now. Was told they rarely go faulty. But I will try changing the map sensor and see how we go.

 

Fuel pump is only 4 months old roughly, purchased and modded by tscomp so I don't really see the fuel pump being faulty if the car starts, drives and idle when cold. Issue only comes when the car is warm.

 

Thing about electronics is it doesn't matter how new or old it is. If it's good then it's good. My omni was on my car for less than 3k miles. I rarely drove the car but it turned out to be bad. I exchanged my 3 months old fuel pump thinking like you the omni rarely goes out but the fuel pump was not the problem. It might be the omni. I cleaned the small hole that the omni uses but still needed the new omni sensor. The ecm gets signal from the map sensor to activate the 12v relay for under boost condition so it supplies enough fuel. Normal driving not on boost the ecm gets signal from cam sensors to activate the lower voltage to the fuel pump so it keeps the engine runing. Goodluck.

 

Wanna bet your lunch money on this?
I say, get you a sensor on the rail near the injectors. Log the pressure on cold start, cold idle. Then log it when you start seeing the problem. Simple, yes?

 

I appreciate the contribution and ideas, I will check if it is the fuel pump but when I had my old dw200 fuel pump and that went on me, it didn't even cause me this many hassles. But I will check it. Thanks. But I think my next step is to heat gun the cam sensor and start the car up cold with the sensor hot, if it doesn't start then found my issue. I have others telling me to check the ground for the wiring to the cam sensor also, so will find those and double check.

 

check the cam angle sensor

 

Iv tried my mates one and it made no change so I was going to get the ground checked by an electrician as the wiring appears to be fine. Correct me if I'm wrong but is the ground wire for everything like the cam angle sensor the big ground wire on the gear box by the radiator hose ?

 

You said you got check light flash. There must be a code to direct you. There's a list of things that could cause issues. You said the pump was modified?

 

I have used evoscan to search for any fault codes and it always comes back saying there is no fault as the check engine light flashing only acts as a warning. Yes the fuel pump Is modded to help with better flow and has been modded by a trustworthy tuner from the states. I should have been more clear about the flashing check engine light, every time the issue occurs with the car dying, the light has never flashed or turned on. It only flashes when I am going wot in 3rd,4th or 5th. So yeah it might be the knock sensor picking up knock but whatever that is causing my issue for the car to die, might not be operating at 100%, so if it was to be a sensor causing all of these issues for me, it could also be causing the knock as it isn't read correctly when it is needed most.

 

Find a good crank position sensor and replace yours with it.









Marios

 

Sounds like the fuel pump is weak while hot. I would replace regardless of age.

 

You have any idea of the resistance of the fuel injectors?