RPM drops when braking, engine lags behind pedal input, clutch leaks, etc etc

[Svarog]

Hello mateys,


I've had quite some issues with my R75 CDT lately, which I think are all related to one and the same thing, or 2-3 at most.

Here's the list of symptoms:
- The RPM drops to 500 when braking in neutral. This is only stopped by pressing down the clutch or braking to a standstil. After the clutch has been used the car seems to be "cured" for as long as I haven't driven it in gear for any distance after that. Often the RPM falls to 600 RPM, and sometimes even to 500..and sometimes it doesn't fall at all. It's utter randomness at it's best.

- The engine seems to be "sleepy" at times. When I press the gas pedal, the engine needs some time to react and the RPM seems to be at unrealistic values (meaning I'm used to have more torque at the given RPM but it's not there. When I pull over and rev up a couple of times while in neutral gear, I can see the effect clearly. I press down the pedal, and a couple of tenths of a second later than usually the RPM goes up. The RPM goes up quite slowly also, and when I release the pedal the RPM keeps on going upwards longer that it's supposed to, after which it again falls to +-750, also in a somewhat slow manner.

- My top speed is 180 KPH. Even when going downhill, with brandnew tyres, empty fuel tank, and no interior (!), I didn't get past 182 KPH. The top speed of my car is listed 191 KPH, and I have reached this speed on multiple occaisons, even reaching 205 (true speed) KPH under conditions far worse than those stated above.

- There is a rattling/ticking sound when letting the clutch pedal come up, or at pulling away at lower speeds. The sound that I'm actually hearing seems to be coming from the metal below my electric chairs, when then gets carried to the mid console through the chassis. The rattling is quite ghastly and drives me mad after a while. Sometimes I even think the sound is coming from my gear box, but I can't say for sure.

- I have replaced the master clutch cylinder at around 238000 km, and the slave clutch cylinder at 251000 km. Both were done by my local Rover garage, who always deliver excellent work.
Today, at 254000, the slave clutch cylinder failed. I got stuck while making a U-turn, and just couldn't believe what was happening. At home I took a look with a flashlight, and saw brake fluid dripping out of the cylinder, and wiped it off with my hand; it's a confirmed slave cylinder leak after just 3000 km, for crying out loud.
This is the 7th (!!!) time in 4 years. Both the master and slave were completely replaced 3 times (this was the 3rd), and another 4 times of filling up in between.
Perhaps this clutch misery can be linked to some other issue?


These are the things that it's about, although I already uncovered the brake/RPM issue being caused by a faulty MAF sensor. But are the other symptoms related to one another?

Any help would be greatly appreciated.


PS: At 250.000 I had the coupling plates replaced (this was done alongside the slave cylinder)

[James.uk]

The MAF could be, and probably is, causing the revs problems.

As for all the clutch probs, it sound like poor workmanship and/or faulty parts..
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[Svarog]

Well, today I had a new Bosch MAF put in, and nothing has changed.
It even got a little worse, which may be due to further deterioration.

Driving become quite abysmal quite often now, I'm starting to get desperate.


Any ideas?

[James.uk]

Disconnect the battery overnight, that might cure the uneven running. But it does sound as though your clutch is not fully disengaging at times..

Also have a look at the switch-sender that controls the revs, it's under the accelerator pedal i think, give it good clean and make sure the pedal isn't jamming against the carpet before the switch is fully operated..

It would also be a good idea to have a look at your PCV filter, it may be gunged up. It lives under the back cover opp end to the MAF. Search for a "how-to" on here for more detailed information.
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