Mot Fail S16

[pug_ham 244 3 Cars]

I've just looked on autodata & surprisingly the voltages to the ATS & CTS are the same at start up (3.2v @ 10'c), voltage to the CTS drops from 3.2v to 0.7v @ 80'c but there isn't any info for the ATS voltage change due to airtemp so if these are wrongly connected that could explain why the emissions were high along with the dead lambda & your hesitation.

 

A quick check with a multimeter for the ATS & CTS plugs will confirm they are connected correctly.

 

The CTS uses pins 26 & 45 & ATS pin 26 (common ecu earth pin) & 44.

 

ECU plug pin layout below.

 

 

g

 

[Jemehan 3 1 Cars]

Thanks Graham. I will check this when i get the chance. I was changing the oil, took it for a run to get it to tempreture (i like to use engine flush) and suddenly she dropped to 3 cylinders, lagged alot worse and started becoming a dragon at the back blowing fire all over the show. Turns out, once i got home and took the cover off, seems a coil pack (cylinder one) no longer wishes to commit to the cause of running an engine. So that will need replacing. Nothing is open today so I will need to wait till tomorrow to get hold of one. Tis a pain! other issue i need to sort is the over heating.

Also tried to get the rev counter to work as per wiring guide for the GTI6, didnt work for me for some reason, soldered the wires in and still nothing, bit of a poop.

[pug_ham 244 3 Cars]

Hopefully the now dead coilpack is the cause of your hesitancy but still worth checking the wiring is correct now you've found some alterations have been made to the ATS wires.

 

g

[pugpete1108 62 1 Cars]

did it fail its mot then dan?

[Jemehan 3 1 Cars]

did it fail its mot then dan?

 

Yeah failed. She overheated before they could finish emissions test...

[Miles 331 1 Cars]

The rev counter is different to the GTi6 so won't work that way I'm afraid, I used a adaptor which just had a couple of Resistors and a Diode in

 

But wiring with iffy Earth tape around would make me check it all out

Edited December 23, 2012 by Miles

[pugpete1108 62 1 Cars]

Yeah failed. She overheated before they could finish emissions test...

Oh dear oh dear. Why's it overheating?

 

You have worse luck than me with cars

[Jemehan 3 1 Cars]

Miles, where can i get hold of an adapter? Also I need to get hold of a T-piece and oil pressure guage sender etc as oil pressure guage doesnt work but the light does. The lack of rev counter is irritating.

 

Pete - My luck with cars, as you are aware has always been a bit pants, think its partly due to me being a bit tight, im putting more money into this one, once its sorted it shouldnt be too hard to keep it there, new coil pak today hopefully. She is over heating as the fans do not seem to be cutting in, this could be due to the on going sensor issues, OR it could be the Thermostat is foobar OR I could just fit a damn fan switch.

 

Also, out of curiosity. I have a fan cowling for 2 fans, however it only has 1 fan in there, i cannot remember from my older 205s if that is standard or if there should be 2. I think 2 may be beneficial, but wondered what other people were running fan wise.

[welshpug 1,657]

the fan wiring is totally separate to the engine wiring, single fan is standard gti fare, no real need for two especially if the rad is good, thermostat works as intended, and there are no leaks

 

there should be a 5 slot brown connector on the fan loom, its a test plug, bridge the centre terminal to one of the outer pair, one is low speed the other high speed.

 

if this works then it'd be wise to replace the fan switch, a few quid at your local motorfactor, check the colour of the plastic ring around your switch, this gives a quick indication of switching temperatures without having to remove it to read what's stamped on the spanner flats.

 

As miles mentioned, it would be wise to pull the loom out and check its condition and that it's connected to the correct sensors, the picture you posted of the inlet air temperature sensor is rather dubious, not only because of the tape but also the incorrect colour of the plug.

Rev counter, depends on the type of adapter, but you can use the same type I have made on S16 and gti6, as well as MP3.1 8valve turbo etc.

[Jemehan 3 1 Cars]

Do you have a link to the ones you have made? Would be a real help to have some kind of guide.

 

As for the Fans, I will have to test the brown plug, I think its still there next to the Rad, Odd thing is the fan used to work intamittantly. Never mind, I will prob fit a back up manual switch too. Incase i get stuck in traffic and it plays up. Plugs i have found so far are like £25. Itll have to wait, Ive spent quiet a bit this month on the car, and my money has to last until Jan.

[Miles 331 1 Cars]

All XU10J4R engine's should have the sender on the block so it's a case of wiring it in

[Jemehan 3 1 Cars]

Update on my situation.

 

I today got my new coil pak as one went last week. Put this on has solved my misfire, un surprisingly. However, the bogging down issue seems to be no better. Infact I had the car on the driveway trying to see if the new misfire was down to perhaps one of the other coil paks being dud and revved the car, removing one coil at a time. Then, while all the coils were attched the car bogged as i was under the bonnet. I am now not sure if this is a coil pak issue or something someone else may have come across? I revved the car harder when it bogged and the car simply cut out? Anyone know what could cause this? Would it possibly be another of the Coils messing about and breaking down causing this.

The bogging normally happens as i put load on the engine, never just on idle. Any help on this would be appreciated.

[Jemehan 3 1 Cars]

http://forum.205gtidrivers.com/index.php?showtopic=144780

 

Found this post... I think it may be worth a shot?

[Vili 18]

Try disconnecting the battery or the ecu. S16 ecu has learn function in it, so idle values just may need resetting.

[Jemehan 3 1 Cars]

I had tried that previously to no avail. I have now bought a new throttle body with associated sensors. So hopefully that will fix the issue. If not then perhaps change all the coil pals.... But that won't be cheap... Shame there isn't a way to test them really....

[welshpug 1,657]

there is, if they make a spark, they're good, if they don't, they're dead/dying, it is that simple!

 

you can also test resistances.

[Anthony 1,003]

That's not really true though, is it? Coils typically aren't digital in their failure mode, in that they don't either work perfectly or not work at all.

 

Perfectly feasable to have one that works fine 99% of the time, but that will give issues intermittently or only under specific situations.

 

Testing them for spark in free air really isn't a good or conclusive test IMO.

[welshpug 1,657]

I agree, however if an issue arises, its quite easy to diagnose if its the coil itself that is causing the issue.

 

With my 405 I experienced an intermittent miss that came and went which was affected by heat soak, eventually it misfired from cold.

 

 

Similar story with DrSarty's ZX, was fine from cold but as soon as it got near operating temp it would start missing under load.

 

 

 

Amusingly for that week we put the coil in the freezer a few times and used binding wire to secure them instead of the alloy cover plate, got us a little further !

[Jemehan 3 1 Cars]

Well this is the problem, S16 has 4 coil paks. I have replaced one that died, i know this as it stopped working all together, but the others could be dodgy and there is no sure fire way to know which one is playing up intermittently unless you replace them one at a time and take it for a spin. I am hoping changing all these sensors will help solve the issue. however if not it will then be changing each of the other coil paks.

 

 

 

I put my foot down and it just stops all accelleration and feels as though she doesnt fire at all... complete bog down, then when you let off the accel it gives a lovely backfire. Strange thing i get with it is it rarely bogs down when you are on the clutch/out of gear, only had that once and its cut out due to it. Tends to be worse at lower revvs. If this sounds like anything anyone knows about please say. I still convinced its likely coil pak but again, which one!?

Edited January 2, 2013 by Jemehan

[Jemehan 3 1 Cars]

there is, if they make a spark, they're good, if they don't, they're dead/dying, it is that simple!

 

you can also test resistances.

In answer to this... they all spark its an intimittend faliure / missfire

[Anthony 1,003]

My gut feeling however is that it's something relating to the recent work around the inlet area.

 

Whilst not unheard of, it seems too coincidental to have two coilpacks fail immediately after working around the inlet area, and logically it is more likely to be related in some way to something that was touched during, or in the vicinity of the work you carried out immediately before the issues started.

 

It's all too easy to forget to put a bolt back in, to fit two plugs around the wrong way, or to damage/dislodge something nearby.

 

A single coil failure would not, in my opinion/experience, result in symptoms as severe as you're experiencing - normally worse case is that it'll just drop to 3 cylinders and whilst rough, should still accelerate and respond to a degree. Back fire does suggest unburnt fuel in the exhaust though, although that's not to say that it's there becuase of a lack of spark.

[pug_ham 244 3 Cars]

I put my foot down and it just stops all accelleration and feels as though she doesnt fire at all... complete bog down, then when you let off the accel it gives a lovely backfire. Strange thing i get with it is it rarely bogs down when you are on the clutch/out of gear, only had that once and its cut out due to it. Tends to be worse at lower revvs. If this sounds like anything anyone knows about please say. I still convinced its likely coil pak but again, which one!?

Has your car got the correct tps because Brian & I had a similar issue on our MP3.1 converted cars, they run fine & would pull through the rev range fine until you asked for WOT when the internal switching on the TPS switched to the idle map, effectively putting the brakes on but if you lifted away from WOT would take off in fine fettle.

 

http://forum.205gtidrivers.com/index.php?showtopic=141287

 

g

[Jemehan 3 1 Cars]

I would have assumed the TPS is the correct one, I have a new throttle body on the way now too incase the one i have has failed. The car has not had any inlet sensor changes for over a year and the issues have arisen lately. so i am not sure if the TPS is the issue or now, I am changing most of the sensors around there to try and resolve the issue. I believe the Cam poisition sensor is fubar too as the car takes ages to crank over before starting, this and when you disconnect it, it makes no difference to anything at all, even when you try to start. Again, I have a replacement on the way. Hopefully this lot will sort the problem and i will update you all as soon as i have all the new parts fitted.

[Anthony 1,003]

Taking ages to crank over to start is often a sign of lack of fuel pressure at the rail, usually from a faulty return valve in the in-tank pump.

 

Basically, you're having to crank the engine over for long enough for the fuel pump to re-pressurise the fuel rail before there's sufficient pressure to inject sufficient fuel. Usually once it's started, you can switch off and it'll start again on the button within a few minutes, but not when left for an extended period.

[pug_ham 244 3 Cars]

OK, try the new TPS & see, they can fail & this could be your problem.

 

Brian & I suffered the problem using a 405 loom with a ZX throttle body & tps which has different internals so we had to alter the wiring, unless your conversion was sourced from the same car it could've been an issue but as its only recently started doing it I doubt the wiring / TPS mixture is the cause.

 

AFAIK if the cam position sensor was fubar, it wouldn't start at all because the only time this sensor reference is used is during cranking / starting. They can be tested but you need an oscilloscope for this.

 

Depending on who did the wiring it is possible that the fuel pump doesn't give an initial burst to prime the system for starting, can you hear the pump run brielfy when you turn the ignition through to position 2 before you start it?

 

g