T4/TOAF Question - Page 3

pletevl · 9th April 2019, 07:08

Quote:

Originally Posted by mbonwick

That's what I thought as well, unless it's something car specific.

It runs too rich at idle (likes to throw P1300 and P1316 codes with random multiple misfires thrown in sometimes too), but then seems to be a bit lean up the top of the rev range (which is not unexpected I guess).
Should add that it starts no bother, and runs OK until it goes open circuit control, then is awful before it goes away again as it gets warm. Runs fine when hot.

Compression OK, timing OK, no air leaks, coolant & oil temp sensors OK. pscan livedata shows nothing obviously amiss either so I'm at a bit of a loss really.

mbonwick,

little question, as I have a ZR and a TF with the same problem.
When you first start it, when it's cold, does it run OK for 30 odd seconds and then start playng up ?

Pete.

mbonwick · 9th April 2019, 19:37

Ben - definitely not the IMG as it has a VVC metal manifold fitted.

Pete - that's pretty much exactly what it's like. Maybe not 30 seconds, but it starts OK, runs OK for a bit then develops the miss.

Now, twice today it's also had a misfire when hot. Codes only relate to cylinder number 2. So I pulled the plugs, and sure enough the other 3 look fine, but no. 2 is very wet and sooty.
Shine a torch down the hole and can see fluid on top of no.2
Let it dry out then do a compression test - comes back marginally higher for no.2 which is wet again.
Swap coils & plugs around, run for a brief period - again no.2 wet.

Thinking I might have a sticking injector? Surely if it the fuel pressure regulator was leaking past no.1 or even no.3 would show some evidence of overfuelling? Even when I ran pscan in BMW mode it was only no.2 that showed up a misfire count.

pletevl · 10th April 2019, 13:09

Here's a thing to try.
When it's running bad, stop and turn off the engine. Restart it and see if it is still playing up straight away or when the lambda readings are taken into account, which I believe is about 30 seconds after start up.
Unless I'm wrong !?!?

Pete.

mbonwick · 13th April 2019, 15:45

That used to work Pete but increasingly it would struggle to start again.

Following on from Tuesday's diagnosis, I replaced no.2 injector which so far has made a massive improvement...watch this space.

It's still not 100% smooth at idle but I'm not going to poke further until I get the exhaust mounting rubbers replaced to rule that out as the vibration source. (It's making a noise so definitely fouling the tunnel braces)

9th April 2019, 19:37	#22
mbonwick Gets stuck in Connoisseur SE 1.8 Auto Saloon Join Date: Jul 2015 Location: Kendal Posts: 633 Thanks: 129 Thanked 176 Times in 147 Posts	Ben - definitely not the IMG as it has a VVC metal manifold fitted. Pete - that's pretty much exactly what it's like. Maybe not 30 seconds, but it starts OK, runs OK for a bit then develops the miss. Now, twice today it's also had a misfire when hot. Codes only relate to cylinder number 2. So I pulled the plugs, and sure enough the other 3 look fine, but no. 2 is very wet and sooty. Shine a torch down the hole and can see fluid on top of no.2 Let it dry out then do a compression test - comes back marginally higher for no.2 which is wet again. Swap coils & plugs around, run for a brief period - again no.2 wet. Thinking I might have a sticking injector? Surely if it the fuel pressure regulator was leaking past no.1 or even no.3 would show some evidence of overfuelling? Even when I ran pscan in BMW mode it was only no.2 that showed up a misfire count.

10th April 2019, 13:09	#23
pletevl Posted a thing or two rover 75 cdti(rhd), MG ZR(lhd), MG TF(lhd), MG TF(rhd), mini mpi (lhd), Renault megane III (awful) Join Date: Mar 2014 Location: East of France Posts: 1,282 Thanks: 124 Thanked 114 Times in 93 Posts	Here's a thing to try. When it's running bad, stop and turn off the engine. Restart it and see if it is still playing up straight away or when the lambda readings are taken into account, which I believe is about 30 seconds after start up. Unless I'm wrong !?!? Pete.

13th April 2019, 15:45	#24
mbonwick Gets stuck in Connoisseur SE 1.8 Auto Saloon Join Date: Jul 2015 Location: Kendal Posts: 633 Thanks: 129 Thanked 176 Times in 147 Posts	That used to work Pete but increasingly it would struggle to start again. Following on from Tuesday's diagnosis, I replaced no.2 injector which so far has made a massive improvement...watch this space. It's still not 100% smooth at idle but I'm not going to poke further until I get the exhaust mounting rubbers replaced to rule that out as the vibration source. (It's making a noise so definitely fouling the tunnel braces)