Annoying idle and starting issue

TRIND-FD · August 05, 2012, 12:56:08 PM

I take the apexi has been in for a while,

wiggman2030 · August 06, 2012, 12:22:01 PM

Umm yeah it\'s been in there for about a year now. Could it be running too rich do you think? I Just thought of something. My heat light is flashing on the apexi. It\'s telling me that the Oil metering pump is not working properly. Im currently premixing at the minute to compensate. I checked the apexi power fc manual and it says that if the light is flashing at a rate of 1 second on and one second off (Like mine is) then it\'s either the injector duty is too high (which mine isn\'t) or the MAF sensor is maxed out. I guess that would be the MAP sensor on the 3rd gen. I unplugged it and it ran really badly so I assume that it\'s all ok.

The car seems to have developed a habit of cutting out after 3 seconds of starting it up from cold now too :-( sometimes it does it twice. I think the problem is getting worse.

Annoying thing is.. The car still drives and pulls perfectly fine apart from the revs dropping too low sometimes on idle and the starting issue. Seems to pop a lot more now too.

I\'m running out of ideas. I don\'t want to travel 200+ miles to get someone to look at it when it could be something simple. Ooh the joys of owning a rotary ;-)

wiggman2030 · August 09, 2012, 08:45:44 AM

leading coil pack? lol leading plugs are black and sooty trailing are half black half brown...

Rotormotor · August 09, 2012, 08:57:50 AM

If your apexi has been fine for a year and no other changes have been made recently, it sounds like a faulty MAP sensor.
This could give you a rich idle and poor running as the engine would be running on the wrong part of the fuel and ignition maps.
Could also be a sticking Idle control valve. This would give the same symptoms.
The Apexi is notoriously bad for stable idle though.

wiggman2030 · August 09, 2012, 08:14:40 PM

Quote from: Rotormotor;832252If your apexi has been fine for a year and no other changes have been made recently, it sounds like a faulty MAP sensor.
This could give you a rich idle and poor running as the engine would be running on the wrong part of the fuel and ignition maps.
Could also be a sticking Idle control valve. This would give the same symptoms.
The Apexi is notoriously bad for stable idle though.

Yeah that\'s what the apexi manual says. I would have thought that the car would run badly as well though. Mine seems to run fine but wont start first time when warm and the engine almost stalls when the revs drop. Once the idle stabilises it does sit fairly comfortably at 1000rpm. It\'s just that when you turn it on it bounces all over the place and seems to want to stall a lot. I could change the map sensor but I don\'t really like buying bits hoping that it will fix it lol. Thanks for the input though. I might try to source a map sensor as i\'m getting slightly annoyed with it now :3Confused

Indian · August 12, 2012, 02:57:56 PM

hhmm. have some of you even read what the op is actually experiencing? It sounds like alot of you are rambling about the first thing that come to your head and not take in to consideration the symptoms the car is experiencing...smh

Anyway, OP
seeing that your car is hard to start after it is warmed up, there can be several issue that will cause THAT particular problem.

These are the things to check, make sure you are getting spark to the coils, expecially the trailing , once the problems starts to occur. I would suggest that you get a compression check as many times, this is the sign of seal failing/sticking, loosing compression when warm will cause these symptoms..this is from experience.

Does the car, once up to temperature start to stumble after warm? You might want to check your voltage to see if it dropping off, and take a look at your injector duty cycle.

Touching the ECU parameters should be the very last thing you should do!!

To check your map sensor, the easiest way is to unplug the vacuum line going to it and cap the side that is going to the engine. If there isnt any changes to idle, then you have a map sensor problem.

wiggman2030 · August 13, 2012, 08:54:35 AM

Thanks for that Indian,

I\'ll go to mazda to get a compression test done, I hope it\'s ok as it was rebuilt about 6-7000 miles ago.

As for when it\'s warm (from first start) the car seems perfectly normal. The idle is fine and there are no problems. It\'s once the car is shut off the problems start happening. I will check the Map sensor like you mentioned and get a compression test done anyway as i\'ve never had one. I\'ll post the results once I get them. I take it Mazda are the only people who can do it?

Thanks for the help :-)

wiggman2030 · August 13, 2012, 08:55:06 AM

Oh I\'ll check for a good spark too lol :-)

davehg · August 13, 2012, 09:32:08 AM

Where was it built? Seems to be alot of engines having issues around that mileage recently

wiggman2030 · August 13, 2012, 09:41:52 AM

It was rebuilt by Steve Rivetts. Its now out of warranty though. I really don\'t want it to be the seals :-(

davehg · August 13, 2012, 10:20:26 AM

I hope it\'s not either...I have a Mazda comp tester and can bring it to pod if you want it testing

wiggman2030 · August 13, 2012, 11:07:52 AM

I would have gone to pod but I didn\'t want to risk taking the car out. That would have been great though mate. I will ask around the local area. I believe Jimmy\'s is quite close so I\'ll try them. If not it will have to be Mazda. Thanks anyway. I\'ll let you know if I change my mind about pod as it looks pretty awesome lol.

Indian · August 13, 2012, 04:20:18 PM

Wiggman, when did you notice this problem? did you have the car in storage?

What you should do, is check the stuff I mention just before and after the issue starts.

Also, a easy way to check the injectors for consistency, is after the car dies. Do not try and start it back, pull the plugs and see if any are flooding/burning right.or very dry. Being dry and "clean" will tell you that you are not getting fuel at that point .. I dont know how green your "mechanical thumb" is, so Im telling you the simplest ways of checking without pulling your car to pieces.

wiggman2030 · August 13, 2012, 05:58:55 PM

Quote from: Indian;832722Wiggman, when did you notice this problem? did you have the car in storage?

What you should do, is check the stuff I mention just before and after the issue starts.

Also, a easy way to check the injectors for consistency, is after the car dies. Do not try and start it back, pull the plugs and see if any are flooding/burning right.or very dry. Being dry and "clean" will tell you that you are not getting fuel at that point .. I dont know how green your "mechanical thumb" is, so Im telling you the simplest ways of checking without pulling your car to pieces.

Thanks :-) I\'m actually a mechanic but this car still confuses me lol. I have checked the injector duty on the power fc commander and it never seems to get above 70%. The vacuum seems to sit anywhere between 350mmHg and 410mmHg now when before it was always about 380mmHg. I checked the plugs once on shut down and the leading plugs were both black, dry and sooty while the trailing seemed to be dry and half black, half brown.

I checked at mazda how much it would cost to do a compression test and they quoted me Â£80! lol. I think i\'ll look elsewhere for now. As for the other things. I haven\'t checked the spark or map sensor yet. I not sure if it\'s compression related because if I start the car up within 10 minutes of shutting it off it does start fine. It\'s only if I leave it for a while. Most noticable after 1 hour (once the coolant temp reaches below 60 degrees). I\'m guessing if it was compression related then it would do it whenever I tried to start it from warm... Im not sure though :3Confused

The idle doesn\'t ever seem to play up until the car is shut off which is also confusing. I will definately let you know how I get on with the spark and MAP sensor. Also would a video help? I could post something on youtube so you can see what I mean.

Thanks again everyone, I appreciate the help from you all :-)

wiggman2030 · August 13, 2012, 06:08:00 PM

I forgot to mention I noticed this problem after the OMP died. I took the elbow off to unplug and plug the OMP connector again to check for rust and bad connections but everything was ok. I was hoping it was just a bad seal on the elbow to the throttle body. I replaced the gasket and used sealer on the gasket just in case but the problem still persists. I started premixing as soon as the Light started flashing on the dash so I don\'t think any damage could have occurred. I have tried unplugging the MAP sensor (which made it run terrible) and I\'ve checked for vacuum leaks but due to there being so many hoses I didn\'t really find anything. I have noticed that the car has had trouble starting before hand. A change of the plugs fixed that but they only seemed to last about 3000 miles which doesn\'t seem a lot for platinum plugs? This time the car is just awful to start and the idle is being effected too which it didn\'t before. Sorry I go on a bit but I\'m starting to lose hope lol.