11 replies to this topic

[coyttl]

If course, as I go to post this, I now can't remember the name of the sensor.

Ah, anyways, after having a few problems earlier with my fuel pump cutting off, I figured it was the relay coil pack. (In short, while driving down the road, the engine would just lose power. If I push in the clutch, it'd stall. Basically, I found out that the fuel pump was intermittently cutting out for anywhere between .5 sec to 3 sec at a time. As long as I kept it in gear, the pump would just kick back on and I'd take back off. Now, with it being intermittent, it was rare - in the fact that it first happened a year ago, and then didn't happen for about 6-7 months. At all. Then it started again this past March, off and on.

At one point I stalled due to this, and instead of just hoping it'd kick back in, I hot-wired the pump to my battery.

So, for the last few months, it's been hotwired. And it hasn't cut out at all. Of course, I don't know that it wouldn't have if it was still connected up to the relay pack, either. (My plan was to get a light and connect it up to the feed, and just watch, see if it ever cuts off. If it does, move up the line and try again.)

However, a few days ago, I turned on the fuel pump, get in and try to start it. It wouldn't start. So I had a friend turn it with the air filter off, and find out that the injector wasn't firing!

So, reading the "Sprocket's Guide to How the World Works", I know that the ECU turns on the injector when it senses motion on the flywheel sensor. Is it possible my sensor's dirty, bad, cleaning? How often do those die? Or, conversly, how likely is it that my relay pack's bad? The car's a '92, and everything relating to this is original..

Thanks in advance, everyone.
Mike.

[minicooper1.3i]

Hi

Have a look through this post of mine (if you haven't already) and see if it helps.

Post back either way!

[coyttl]

HCheers!

yeah, I had read yours, and was going to work on that this weekend - if I can. See, mine is SO intermittent that it may work fine this weekend and for the next month, before the problem arrises. I'd have to spend £80 on a new relay pack when it MAY not be a problem. (Yes, I'm an 'American', and I know how to type the £ symbol. Ain't I special!) I *WISH* I had a scrap yard over here with Minis in it!

[coyttl]

I'll add that I DO know it's NOT the pump - as the only time it died long enough to strand me, I got out and hotwired it to the battery, it ran fine then.

[wardy23]

we have a problem like this but the difference is our pump is on all the time, who ever had this mini before has permently wired our pump up through the relay box on the left handside of theengine bay when you look at it from the front
could this be why our spi is running rich and eats a little bit of fuel and blows black smoke out of the exhaust?????

[Sprocket]

I'll add that I DO know it's NOT the pump - as the only time it died long enough to strand me, I got out and hotwired it to the battery, it ran fine then.

Itts no tthe crank sensor either then, as the engine just wouldnt run or you would still suffer the same problem

[coyttl]

I'll add that I DO know it's NOT the pump - as the only time it died long enough to strand me, I got out and hotwired it to the battery, it ran fine then.

Itts no tthe crank sensor either then, as the engine just wouldnt run or you would still suffer the same problem

Well, like I said, there's a catch. (There always is!) I tried starting it two weekend ago, and it would crank. The fuel pump was running (hotwired, could hear it!) had the air box off and had a friend try to crank it. The injector wasn't puling, so the engine wasn't getting fuel.

In my mind, it points to the relay box, or the ECU not turning on the relaty box. (So.. bad ECU or bad crank sensor.)

Can the crank sensor be cleaned? (And if so, would that hurt it?)

[BoyracerAU]

I don't know the lie of the land as regards the crank sensor, but one mechanic told me that they often just pour a cup of water over it in situ whilst the car is running. If the car starts spluttering, odds are the crank sensor is faulty.

My car had a faulty crank sensor. The fault was very intermittent. The car started and ran perfectly fine, hot or cold. It only developed problems once it was fully warmed up. The problem was a complete reluctance to rev above 1,700rpm - only when it was fully warmed up and even then not immediately and not always. One minute you'd be happily cruising along at 3,000rpm. The next minute the revs would drop to idle speed and the engine wouldn't rev above 1,700 for anything. If I tried, I'd just get a lot of popping and farting through the inlet manifold. Unusually for a faulty crank sensor, it only ever completely cut out on me once throughout all those dark months.

One mechanic did have the crank sensor out and pronounced it to be sound and of good health. This ended up being a bum steer and caused me to look elsewhere for another couple of months.

By the way, I'm very new at all this, but I thought information from the crank sensor dictated timing, not the injector. Have I got that wrong?

[coyttl]

I *THOUGHT* That the ECU looked at the crank sensor, and whenever it saw the engine turning, it enabled the injector. I'm THINKING I read this in one of Sprocket's write-ups, but I'm late at the moment, so I can't go back and check.

Working on the train today, and late already. Great.

[BoyracerAU]

Don't mind me. It seems we're both right. Good luck with getting it right.

Copied this post from CMICE from another thread:

Ignition timing and fuel delivery are both controlled by the ecu. You've replaced that (with a known good one?) and you've gone from not starting to barely running...which in my mind means the problem is related to the ecu but elsewhere in the system (ie. sensors or wiring). Would not be something mechanical (ie. failing fuel pump or who knows what).

If the ecu is getting proper signals, fuel delivery should not be a concern...the ecu itself is extremely accurate when it's running correctly. So don't try to "adjust" anything there...there's really nothing to adjust. You did blow out the vapor trap prior to putting the new ecu in, yes?

The popping is an important symptom. Can you tell if the pop is a mechanical pop (ie. a mechanical binding and breaking-free? like a throttle linkage?), an electrical pop (ie. ignition coil that's shorting out? or arcing inside the distributor?), or a combustion pop (ie. a backfire you can hear inside the aircleaner)?

To me, from only the video, it sounds like a backfire through the intake. With a clear ear inside the engine compartment (ie. have a friend rev it while you listen carefully), you should be able to locate it. A piece of hose up against your ear makes a handy stethescope for locating hard to find noises (just don't blow your eardrum out).

Unless your cam timing has changed (ie. a skipped chain or a lobe has fallen off), the only way backfires happen (that I know of) is incorrect ignition timing. It is not adjustable as it's driven by the ecu. Either the crank-angle-sensor has gone bad, connector(s) is dirty, the rotor is incorrectly installed on the distributor shaft, there's debris in the cap, or you've got cracked ignition wires allowing for cross-firing. Check and clean all connectors related to the fuel injection (ecu, throttle body, and grounds).

[minicooper1.3i]

Am interested to hear how this one gets resolved, as I drove a car the other day which wouldn't rev over 2000 when warmed up. I was told that the crank position sensor had been replaced. But then I was also told that it was done by the local Citroen garage

With regards to the relay pack, you can get them, and most of the other sensors from most other 'K' series engined Rovers. My replacement (which I didn't need) cam from a '95 Rover 400.

Keep the posts coming folks

[coyttl]

Thanks you two!

Since the Mini won't be drivable next week (rims are coming off to get an estimate on changing them to black), I may take up an offer I had to have my ECU sent over and tested / checked. Being in the US, money's an issue (no comment, there) so I'd rather not replace everything wily-nilly.

Hmm.. maybe I can post a wanted ad for a relay pack. Can't hurt, right?

Cheers,
Mike.