Haakon

I got a dead stock JDM 93 FD. And i have one of those "5000rpm" problems. However my problem differs from other ones i have read about in this forum. It just wont go past 5000rpm whatever i do.

In all gears, in neutral, gearing down to get it in higher rpms it just dies until it goes under 5000.

It works just fine in lower rpms though UNLESS for some seconds after i hit the 5000rpm wall. For example when i hit this wall in 1st gear and gear into 2 gear and hit the throttle, the car seem to loose some power for some seconds. If im careful not hitting this 5000rpm wall before gearing it works just fine.

Nothing wrong with the boost pressure, tried replacing all injectors, tried new plugs, checked the ignition coils, plug wires, no ecu codes triggered..

help!

DaleClark

iTrader: (55)

Could be one of 2 things.

First, make sure your double throttle actuator isn't staying shut. It's the second set of throttle plates in the upper intake manifold, by default the ECU holds them shut when the car is cold to keep the driver from getting into power on a cold engine. If they're staying shut, you'll get all sorts of no-power problems.

Next is the ignition coil harness. I've seen bad ones do WEIRD stuff like this. If the harness on your car has a ground wire that attaches to the coil packs, it's the old one. The new one doesn't have that ground wire.

Dale

Haakon

Thanks for the reply!

I will check out the throttle plates.
As for the ignition, i have measured the coils and plug cables, and checked the harness for damage... I dont know what more i can do

Strange thing is that the car starts and runs perfectly up to this rpm

btw, forgot to mention that it sounds like a rev limiter, with some backfiring..

JTurtonRX_7

do you have a power fc? any time I leave my car to get inspected or new tires on it i set the rev limiter to 3.5k. Its a long shot but your rev limiter just might be set to 5k.

Haakon

No power fc, the whole car is stock.


There was many problems with this car when i bought it. One reason i got it cheap

So far i have replaced some faulty injectors, rewired two solenoids (faulty wire from ecu (!!)),
one of them was this purge control solenoid where the solenoid also was broken.

Hope to get it running properly soon.

JTurtonRX_7

Some people might disagree with me because they will say its dumb to pay for a stand alone on a stock car with problems but, Id pick up a power fc and datalogit. Anytime I have a funny electrical issue i just fire up the datalogit and run a log of every sensor and go out driving.

One time I had this completly random crappy idle and loss of power and sometimes stalling out. Fired up the logs and I quickly found out that my engine coolant sensor would randomly jump down to -32 degrees so it would be dumping way more fuel than needed. Turns out the wires going to it were frayed and touching each other.

Haakon

Yeah, i have been thinking of getting a power fc. I bet i would find the fault im having in a second with it..

Haakon

...after alot of searching and testing i checked out the crankshaft position sensor. There i discovered something really interesting. The plate wich the sensor feels on is bend out a good 1cm in one place. Could this be the reason for my problems?!

Haakon

i gave it a good beating with the hammer to straighten it up, and it did the trick! the car runs perfect for the first time!!

Who thought after months of problem searching, all it needed was some work with a hammer!!

JTurtonRX_7

haha , i laughed when i read the post then looked at your new avatar. Thats jeremy clarkson right?

congrats on figuring out your issue

DaleClark

iTrader: (55)

Glad you found it! BTW, down the road you might have to replace that wheel. If you get a PowerFC, they're much more sensitive to having a perfectly straight trigger wheel. Good thing is a good used trigger wheel is a dime a dozen.

Dale

Haakon

thanks, yes thats clarkson with his favorite tool

i will replace this weel as soon as possible

Ceylon

iTrader: (3)

Haha - Glad you got it fixed.