Help desperately needed - intermittent problem on SP20 (Perth)

[SPtwenty]

Hey guys!

I've just been referred here by a member from astinagt.com as there may be more Perth members here. I need help with my car, I am at my wits end. I have a 2003 SP20 (auto) with an intermittent problem. I've had the car for a year and all was well until probably the fourth/fifth month. One day the car's engine just cut out on me while I was parking the car. Okay I thought battery (car didn't start up again), RAC comes out, battery is fine, RAC guy doesn't know what's wrong, drove it one minute and again while parking it cuts out, calls another RAC guy who knows more about electrics. He comes out, has no clue, car starts up fine, drive home.

Maybe another two months later and it happens again, this time while driving at 80km/h. SCARY! Everything shuts off and I'm lucky to pull over into the service lane as brakes don't work (only hand brake). RAC is called again, two guys check it (car has now started), he revs it for ages, car is fine, I drive home. Being a bit scared now, took it to an auto electric shop, they had it for a day, couldn't replicate the fault therefore could not diagnose a problem. Great.

This time I ring Mazda who wants to charge me an insane amount of money just to check the car with no promises. Rang another Mazda dealership, they don't know what an SP20 is. Enough said. Anyway, again, wanted some insane amount of money and were really not interested after mentioning it was a 2003 model. And I plan on staying away from another dealership who I think has been mentioned already on the net.

Okay, so driving again and it happens about 6 weeks/2months later. Again, at a carpark but this time when idling (was looking for a shop). Tried to start it up, it chugged and then managed to start it so I could reverse into a parking bay, and then it cut out again. This time I didn't try to restart it. Anyway, RAC guy comes out, he gets out his diagnostic tool, it says engine misfire. Doesn't help because it could mean 1000 things. What a useful tool. Anyway, he lets the engine run for a fair while and was about to leave as he couldn't get it to fault when lo and behold, it dies. He again gets his tool but for whatever reason he says it didn't log a fault, it went away too quick (whatever that meant). Now he saw with his own eyes what happened as the hood was up. It looked like the engine was convulsing and about the jump out of the car and then dies. This is what it also felt like all the other times it stopped, the revs drop/flutter and then it shudders and dies (felt from inside the car). RAC guy thinks that it was being starved of fuel (engine coughing), he thinks fuel pump but not sure. Could be heat related problem he says as I was driving and stopping a lot (engine has not overheated at all on the gauge). At least something.

This time took it to a mechanic, he had a good look, said car was fine, not replicating any faults (grrr). Again, maybe fuel pump, maybe not. Can't check as inside tank. So other than that, my car runs fine, everything is awesome, except it has failed on me three times. Car had a major service as I bought the car, water pump was replaced. Other than that, just standard. Recalls done.

Does anybody know what is wrong or who is reliable/smart enough (preferably North of the River in Perth) who can help me? I've already spent a mini fortune taking it to places and getting it towed only to find nothing useful to go on. I just want it fixed because I love this car, it's awesome to drive. I've tried to give as much info as I can, the only other thing I can say is that at times, the car may take a few chugs to start but it doesn't happen everyday so think it's just normal? Usually starts first time. I don't have a lot of money but don't mind paying to fix it (provided that the problem is found and fixed), I just don't want to be playing Russian Roulette with the car. Maybe someone can help me as this is my last hope.

Any help is appreciated and thanks in advance for taking out the time to read this.

Cheers!

[240MPS]

Does this happen with close to empty tank ???? If I recall I had a similiar problem with the mrs celica with the fuel filter in the engine bay needing replacing. This is back in the 80's, use to cut out and splatter when driving .... Good luck with the fine...

[2XS]

The cheapest, check all the wires are intact (not rubbing on CVs or drive belts etc.)

2nd cheapest, but, most time consuming job, Buy a can of WD40 or CRC, remove every single plug/connector in the engine bay and clean them. It could be just a small amount of corrosion. You may even find a loose connection while you are there.

I had a Magna that had the Crank angle sensor wire rubbing slightly on the drive belt, it wore through and then stopped randomly. But, it would start again, usually. I only noticed it from a chance sighting.

Hope this helps.

[SPtwenty]

Thanks so much for the replies guys!

240MPS, everyone asked me the same question. All three times had varying levels of petrol. First time was a bit more than quarter, second was half and the last time was almost full as I had just filled up that morning.

2XS, I think the RAC guy and mechanic checked for loose wirings but didn't really find anything. The mechanic mentioned checking some wiring regarding the fuel line I think but he said it was all fine. However, he did mention a certain wire in the engine bay underneath the black cover that was squashed so he moved it over but reckons it probably isn't the cause.

The RAC mentioned something about a Crank angle sensor as you have said. I know nothing about checking all these things out (or knowing where they are) and removing stuff so if anybody has a recommendation of people in Perth (north of the river) that could help me and not rip me off, that would be great (you can PM me details). I only know how to check/change oil/filter and coolant. Additionally, if anybody could point me out to diagrams if such exists, that would be great too. I just wish it was something simple.

Cheers!

[Brackaus]

I had a simillar problem with a nissian thingymabob car. It turned out that the fuel line was getting air (it wasn't attached tightly) and it randomly just stopped working like i ran out of fuel. Luckly my brother managed to see it when i rev'd (saw some bubbling fuel). Hoping it's something simple like that.

[rogwick]

Interesting read about your problems mate (and Welcome to ozMPSclub)

I've had some issues with my GF's 2002 SP20 which were intermittent too. I ended up fixing it myself as I had the same problem as you, no-one knew what the problem was or how to fix it! Can I ask...do you experience any "loss of power" (not just sudden shut-down) when cruising? Can you make it up hills ok etc. I was driving my GF's car after she reported it had a problem and at one point I had foot to the floor 1st gear up a hill, only just making it. Max I could do was 50-60kmph on a flat road. Then all of a sudden the next corner I lit up the front wheels and the car took off?!!

If you have any symptoms of the above let me know...

I'm not sure if your problem is similar but seeing my GF has pretty much the same car (only manual) perhaps I can provide some small amount of info. With regards to the brakes failing, that is probably normal seeing the motor has shut down. Not sure how well to explain it but the brakes are motor assisted. They might work for a few pumps after the motor has shut down but very quickly the brakes loose pressure and become very hard to depress and thus very hard to stop the car. If the brakes work fine when the motor is running then I highly doubt you have a braking issue. The same thing happens in most modern cars. Same with the power steering...shut the motor down and the P/S fails.

Just a note, our 1998 Mazda 323 has issues with sudden engine shut down and we found it to be a dirty throttle body, if that is of any use information to you...

[Doug_MPS6]

SP20 & ROG, Hi. Most modern braking systems are power assisted, as is generally required by disc brakes which have a higher clamping force requirement. This assistance comes from a vacuum booster which draws vacuum from the intake manifold. When the engine is not running, manifold vacuum is lost and hence breaking effect is lost. Often there will be some residual assistance after the engine ceases operation, but the residual vacuum in the booster diaphragm housing gradually decays until you have no further assistance. Therefore, if it happens again, use your residual vacuum assistance wisely as it is a finite resource. You will still stop with no vacuum/booster assistance but it will require much more pedal effort than you are used to. Knowing this will prepare you for it and you shouldn't panic if you feel the car is not stopping at all. Just allow more braking distance until your main issue is resolved.

It will help us to know if your engine stoppages are a series of hesitations and/or progressive loss of power or a sudden stone dead cut-out.

If the former it is either fuel starvation or fuel exhaustion (your description of "stumbling and chugging" might point to fuel issues though the latter option of exhaustion seems less likely or unlikely in your case). Blocked fuel filter(s), sucking air though a cracked line or crook union, or a defective pump can give rise to intermittent starvation.

If the latter (sudden stoppage), it is almost certainly electronic or electrical (there IS a difference). I'm betting in that case that if it isn't a crook ECU then the problem is a simple intermittent electrical connection issue, even a bad earth, but given limited info and no physical inspection, I'm prepared to stand corrected.

I don't know the SP20 intimately, but a bit of net research shows it to be a 2 litre twin cam four cylinder with fuel injection. Can you fit a Dashhawk (or similar) that might give you an error code?

[rogwick]

Can you fit a Dashhawk (or similar) that might give you an error code?

Thanks for explaining brakes Doug! Well said. Nope you cannot use the DH. We tried on my GF's car and although it has a obd2 port, the DH is not supported. Perhaps a scantool might work?

[kmh001]

There are a multitude of possible causes of intermittant engine failure. The "coughing" tends to point to a loss of fuel pressure. No body can diagnose of the problem from here, but here are some ideas:

Intermittant faults often have unusual causes, unlike regular failures that can be easily identified by the thing thats no longer working.

There could be an electrical issue affecting the fuel pump, or a dirty fuel filter. There could even be a heap of crap such as sand or rust (or a foreign body) in the fuel tank that moves around and occasionally blocks the pickup. I once removed about two cups worth of rust particles from a fuel tank that came from a dodgy service station.

Another possibility is a crimped or blocked fuel tank vent that can cause a vacuum to form in the tank that prevents fuel flowing to the engine. This can occur after the fuel tank has been out. Has the car ever had smash repairs done at the rear end?

Another possibility is water in the fuel tank. Water is heavier than fuel and will quickly settle at the bottom of the tank. If the fuel pump pickup isn't right on the bottom of the tank the water can exist in there for ages with a bit of it occasionally being sucked into the engine and making run rough.

Instead of trying this or that and spending heaps, it would be better to take a methodical approach to have the fuel system checked from beginning to end. I think the fuel pump needs to come out for a visual inspection and the inside of the tank also needs to be checked. Then the fuel delivery and return lines need to be checked for blockages etc etc.

[Doug_MPS6]

I have a feeling a good afternoon spent checking all electricals, fuseboxes and fuel lines, including underbody lines, might reveal something. The tank location for the fuel pump is a bit of a pest, but it should also be checked. Ditto all plug connectors and feeds. I find a long, relaxed ponder with no time pressures and progressive checking works well for eliminating seemingly intractable issues.

---------- Post added at 11:21 AM ---------- Previous post was at 11:19 AM ----------

KMH001 I think we agree - our posts came through at the same time with the same lines of thinking!!