Stuck at 2500rpm

[Brainfire]

Hi people...

Desperate help required! 1995 FD UK model - HKS induction kit, HKS exhaust, HKS Intercooler, dump valve, 62,000 miles. (No boost gauge)

Over the past couple of months, when accelerating moderately (or hard-ish), normally in second gear, there would be a sudden cut of power, just for a second, then it was fine again. It never seemed to get progressively worse, but it was just consistently doing it.

A few weeks ago, things got drastically worse. Started up and set off, only to find that when I hit roughly 2500rpm, I also hit a brick wall. Trying to go past this point achieves nothing and the exhaust backfires and pops like mad.

After this, it wouldn\'t start. Seems to be flooded all the time. Now it has to be towed for about a mile before it splutters into life. Then, leave it for a day and it won\'t start again.

Took it to a friend who\'s a mechanic (but has only ever seen one rotary before, and says it\'s like a plumbers yard when you lift the bonnet), who had a look. It seems to be constantly flooded. Stuck the analyser up the exhaust and it reads ok on idle, but really rich when revved, but we\'re not sure if FD\'s are like that anyway? I\'m not technical at all, but he said the topmost of the two turbo\'s appears to be pulling nearly nothing in the way of air, even when revved hard. (Strange that it seems to rev over 2500rpm most of the time when it\'s sitting still)? He reckons maybe a valve stuck open somewhere or a hose off. Checked the fuel pump first before anything else and that\'s ok. I\'m hoping it hasn\'t thrown a rotor tip - it hasn\'t been thrashed since the Summer, so I\'m keeping my fingers crossed.

If anyone has any ideas, I\'d be most grateful - and, if possible, is there anyone near me (Dundee, Scotland) or even just in Scotland, who\'s half-decent with FD\'s that could have a look if I got it to them? Just knowing there is someone around would be a great help.

Sorry for the length of the tale of woe....  

Thanks in advance

[Martiny]

It sounds to me like the ecu is in limp mode. Disconnect the battery, hold foot on brake pedal for 1 or 2 seconds, reconnect the battery.

If it goes into limp mode again, we will have to pull the error codes to what the ecu has found to be faulty.

[banned advertiser]

Brian it could be a couple of things.
The cutting at 2500 may have been fuel starvation, why I dont know, could have been a faulty pump, blocked injectors, faulty ecu, faulty map sensor etc, but that would cause detonation which would explain why it wont start now, very good symp of whats happening, get it compression tested, but if you have to tow it to start, I\'d say it was time for a rebuild. When a car detonates it cracks/chips or breaks the apex seals that give it compression, hence it dont like starting it has no compression, but tow it where you can get the rotors travelling at a greater speed and the other apex seals going then youi get compression and it starts.

Other thing to also check are the map sensor, if it has the pipe split or come off can cause problems, its a small black box circled in this picture.

You could try a place called the garage in witshaw up your way, he has seem several FD\'s or the nearest Specialist to you is Pip at WGT as advertised at the top of the forum with his banner.

Good Luck.

[Brainfire]

I\'ll check the map sensor as soon as I can - should the local Mazda dealer (spits on the floor in disgust) be able to compression test it? What kind of readings are we looking for here?

If anyone else would like to offer anything, feel free... some sort of pointer as to where the offending part might be would also be appreciated if you have any ideas.

Thanks

[banned advertiser]

for a healthy engine look for 6.5/7 and above assuming its a stock engine. Post you results

[grinder]

Brainfire :

I have removed your avatar as it was a bit close to the knuckle for MRC

Thanks

Stu / Grinder

[Martiny]

Was fun while it lasted! :-)

[Brainfire]

Hmmm, I still can\'t convince myself it\'s a rebuild job - checked the map sensor pipe and it looked ok. Disconnected the electrical connection on it and gave it a clean, disconnected the battery and jumped on the brake pedal as advised above, then put it all back together again - now the bugger starts first time, every time! Still gets \'stuck\' at 2500rpm though, and doesn\'t idle like it used to until it warms up, then it\'s fine. Hit that 2.5k though, and it goes flat, mega backfiring and popping from the exhaust - guess I\'ll have to get a trailer and tow it the 100 miles to Wishaw to let them have a look unless anyone can think of anything else? Rough price for rebuild at WGT, guys, if the worst comes to the worst? Not that I can afford it just now anyway...

Thanks anyway, guys....

[Gerry M]

You ever find out what was causing this??

[Brainfire]

Yup, the oil metering pump was duff, so it was in limp mode - still can\'t find anyone in Scotland to compression test it, and I\'m buggered if I\'m doing a 600 mile round trip to get it done, so I\'ll guess I\'ll just have to drive it until it drops dead, or gives some other indication that it needs a rebuild.

Buggering thing.... think I\'ll buy a Kia Picanto...

[Gerry M]

was that with a pfc fitted?

[Brainfire]

Na, standard ECU - I\'m sure PFC\'s are wonderful, but when it comes to fault finding, the standard ECU is a great help with the fault codes.