Car Dies While Driving Along!

[starky5 18]

So the last few times I've been out in my 205 I've ended up getting towed home. Ill be driving along no signs of problems and the car just cuts out, it seems to be losing its spark. Ill pull over and it turns over but won't fire. Sometimes if you leave it a few mins it will start again for a bit but normally cuts out again soon.

 

The plugs, leads, rotor arm, dizzy cap and ingnition module are all new and I should have a coil tomorrow but any ideas what else might cause this? Maybe crank sensor?

 

Sorry just thought I best add that's its a mi16 engine running standard injection

 

Thanks for any help

[ORB 227 1 Cars]

Standard injection?as in standard 8v or standard MI16?

[m_attt 31 1 Cars]

have you checked your earths, mainly the strap that goes onto the gear box.

[starky5 18]

Standard mi16 injection, sorry.

 

No ill have a look at the earths this evening see what the connection is like

[Weser 30]

I had a simillar issue (but wasn't losing the spark when I checked) it turned out to be a bad connection on the ecu coolant temp sensor - had a bit of crusty coolant in it.

[TT205 42]

I had an identical problem and it was the dizzy, was very hard to diagnose because it was intermittent

[ORB 227 1 Cars]

I had a very similar problem on one of my old GTi's tried everything to get it sorted, in the end it was a crappy connection to the fuel pump

[Anthony 1,000]

Could be all manner of things judging from the description, but being an Mi16, I'd swap the two relays (swapping for two standard green ones is fine) and check carefully the wiring where it meets the relay holder - the relays themselves tend to suffer badly when in 205's, and the wiring always seems to corrode and eventually break away at the base of the relay holder.

 

Depending how the loom was converted, it's worth checking where the 205 and Mi16 looms are spliced together, as there are some utterly shambolic efforts out there that it's a miracle they work at all, and these seem to give no end of intermittent issues. Having the engine running and wiggling and shaking everything you can will often identify such issues before succuming to another ride home on the flatbed of shame.

 

If you don't already have one, a multimeter to keep in the car and a spare spark plug (to check for spark easily) will help pinpoint the issue.

[starky5 18]

I will check out the relays when I get home then an see what the connections are like, and ill chuck a multimeter in the boot along with the tow bar! I have tried wiggling all the coil, ingnition module and crank sensor connections but they make no difference so ill move on to wiggling relays. I didn't have the closest look at the loom before I put it in but I did re-tape most of it to keep it neat and didn't notice any connections looking to dodgy so fingers crossed the loom will be ok.

 

Thanks for the list of places to start

[starky5 18]

Just a quick one, any idea where the two looms are likely to be spliced together? Going to have a proper hunt round the try and find any issues tomorrow so a starting point would help

[S@m 156]

I had a similar problem on my mi16 and it took a long time to find the issue - in the end i just went under the bonnet with the engine running and gave various plugs and connections a bit of a wiggle, soon found that when you did it to the injector relay, as Anthony mentioned, the engine would cut out. I wired in new relay holders/contacts and it solved the issue.

 

Soon after i went over most of the engine loom connectors cleaning and replacing whatever was necessary, helped no end with reliability.

[starky5 18]

Which is the injector relay? I gave the two that are on my mi loom a good wiggle with the engine running and it made no difference, also the connections to the bottom look in good condition.

 

Life would be easier if the issue became permanent! Would be much easier to find!

[S@m 156]

The one that clicks when you turn on the ignition is the fuel pump and the one that clicks when you crank the engine is the injectors (and a few other things) - thats the easiest way to differentiate without tracing wire numbers.

 

Another area that was dodgy on mine was the two yellow connectors that connect the injectors/icv/cts to the rest of the loom - although mine is a BX loom so not sure if 405 looms have this or if its all self contained - mine were always giving problems so in the end i removed the connectors and hard wired them.

[starky5 18]

I don't remember seeing those yellow connectors when I fitted the engine and loom. I worked out which relay was which and removing one of them replicated my problem identically so I have swapped it for another relay and so far so good! Will source a new relay to replace it and wait and see if I need towing home again!

[huwjones 0]

Are the crank sensors any good on these? I wouldn't exclude it, given its probable age.

[starky5 18]

I did think crank sensor was possible. I have changed the relay that seems to control the ignition and so far so good! Only been out once but it was the same journey I had to be towed home on the other week so a promising start!

[Anthony 1,000]

Good show - as I said in my post above, a failing relay causes exactly this sort of symptom.

The one that clicks when you turn on the ignition is the fuel pump and the one that clicks when you crank the engine is the injectors (and a few other things) - thats the easiest way to differentiate without tracing wire numbers.

Other way around isn't it? Fuel pump only gets powered up when the ECU sees the engine rotating (ie cranking or running), whereas the other relay is energised on ignition on.

 

It's been a while since I played with an Mi16, but I'm sure that's correct.

Another area that was dodgy on mine was the two yellow connectors that connect the injectors/icv/cts to the rest of the loom - although mine is a BX loom so not sure if 405 looms have this or if its all self contained - mine were always giving problems so in the end i removed the connectors and hard wired them.

It's only BX 16v looms that have the multi-part harness - 405 Mi16 looms are nicely self-contained single piece loom that's a more appropriate length for a 205 (and consist of wire colours other than the almost all green BX's!)

[S@m 156]

But i like green! I have noticed that whilst the BX loom is easier to actually get the engine running, the 405 loom is easier when it comes to getting the gauges and lights working imo.

 

I was under the impression that the fuel pump came on with ignition so as to prime the rail, whereas the injectors and such were not energised until the ECU saw the engine rotating, but having checked the wiring diagrams in CAPS it appears you are correct as usual Anthony - apologies to the OP for backwards info there. Since i have been without my mi16 for almost 2 years now i've gotten mixed up - not to worry though, will be back with my beloved D6C in about a months time - and finally in a 205 rather than 306.

Edited May 16, 2013 by Sam306