VR6 very lumpy idle, OBD2 T42 pinouts p.4

[fla 9]

Is there a list of the wire colours on the T42 connector? I just put them all in in the same position as the obd1 positions but I am guessing that it is different for obd2?

[science 0]

I could not find a list anywhere, was going to make one but run out of time for my OBD2 conversion.

 

I've had a look at your pins on the connector picture from your build thread;

[ATTACH]80199[/ATTACH]

Is there something in pin 27?

Other than that, all the right slots are used, but they may not be the right wires.

[Jim Bowen 1]

What would be the symptoms of having the intermediate sprocket 180 degrees out?

[Dox 23]

What would be the symptoms of having the intermediate sprocket 180 degrees out?

 

Lumpy idle

[swiftkid 1]

Yes, thats probably your problem, I havn't been through all the wires but I have noticed various differences in pin placement between obd1 & 2. I can't get to wiring diagrams at work but it may take some time to rewrite them.

 

Picture of T42 plug in this thread: http://the-corrado.net/showthread.php?t=87250

[fla 9]

thanks Swift. I've put the obd2 colours into a spreadsheet from the Golf/Vento diagrams, just cant find what pin 22 should be.

Hoping for success this time!!

 

I've attached the list with some comments as to each pin - might help others.

Edited November 21, 2014 by fla

[swiftkid 1]

T42/22 is coolant temp sensor g62 as shown, should be a blue wire

[fla 9]

great, thanks. I should have added that T42/4 is the coolant temp sender G2, so i guess one is the blue and one the yellow or black, i'll see tomorrow which one is which.

 

edit: T42/22 amended in spreadsheet

Edited November 21, 2014 by fla

[swiftkid 1]

Best of luck tomorrow, drop me a pm if you get stuck

[fla 9]

Much appreciated ;)

 

Well the wiring is all ok just a few colour differences as compared to the list.

Next step is to swop back to my old injectors. Then I'll check the wiring to the coilpack and injectors for continuity.

If the fpr were faulty would this give rise to these symptoms?

[swiftkid 1]

I would start with the basics and work back

-is the wiring OK... Yes

-do I have spark... Yes

-do I have fuel... Yes

 

And then start adding variables in, as Jim says though, have you double checked timing on chain? You can get intermediate shaft 180 degrees out

[fla 9]

All three are a yes. I guess I threw in another variable with the replacement injectors. But from when I was pulling ht leads at the beginning and some having no change on the engine does this point to a suspect injector?

How would I check whether the intermediate sprocket was 180 degrees out? All the timing marks lined up fine...

[fla 9]

What would be the symptoms of having the intermediate sprocket 180 degrees out?

 

what's the easiest way of checking this? As previously, all the timing marks lined up, i could see the slot in the sprocket from the top of the engine, so I'm not sure what i should be looking for..

[swiftkid 1]

Here's the link to chain replacement, also has timing setup. Sounds like you have timing right though. How did you get on with checking wiring? http://forums.vwvortex.com/showthread.php?1264409-DIY-Replacing-timing-chains-tensioners-and-guides-on-a-12v-VR6%5C

Edited November 23, 2014 by swiftkid

[Jim Bowen 1]

If you can see the slot from the top then it's ok.

[fla 9]

Well we're back to normal thankfully. Turns out the replacement injectors I bought were faulty. Put in my original cleaned injectors which I know were perfect. Lesson here : buy new whenever possible! Unless the supplier is someone you know and trust.

Many thanks to everyone who helped.

 

I'll be testing each injector individually and binning any faulty ones.

[Sean_Jaymo 0]

Nice one on getting it sorted.

[swiftkid 1]

Awesome news that! Been out in obd2 goodness yet?

[robrado974 1]

Nice to hear you got it all sorted Hasan .

[fla 9]

thanks chaps :) Swift - not yet, only managed to get about 1 hour on it today, refitting everything back and only then let to it idle on the drive for about 5 minutes. Pulsed the throttle and immediately you can hear the advantage of not having an isv by the way the the idle speed returns.

[Jim Bowen 1]

Is it much work to convert to OBD2? What bits are needed?

 

Only ask as my car is in bits again, just if its worth me doing this mod as well.

[swiftkid 1]

From hasan's bad luck it's a lot of work but overall it's not that bad, everything just swaps over, it's just wiring that is a bit daunting. The only problems I came across was immobiliser playing silly bugger and auxillary water pump that wasn't connected (you need to connect 2 wires from engine plug that wasn't originally written about).

 

I was impressed with the conversion, definitely more power bottom end but it did take away some of that vr kick at 3k as the power delivery is a lot smoother and starts lower down

[fla 9]

^^^^ this. My car would have been running months back if the round connector were ok and the replacement injectors were also fine (just tested them and 2 were dead!). As Dave says the hardest bit is the loom, but if you take your time and follow the steps to remove wiring you'll be fine. The aux pump is not in the loom and needs to be wired in. And you can also get around the immobiliser with a few tweaks. After I've driven it, I'll report back on the driveability.

 

Compared to your work on the rebuild Jim, this will be a piece of cake. Dave and Neal (Swiftkid & Science) are extremely knowledgeable on it and have helped me extensively so should be able to answer any questions you have. I will chip in wherever possible too.

[fla 9]

Just to update this - my MAF sensor was actually broken inside. Bought a replacement bosch one (on exchange from gsf) but it was still around £90. Poor idle has been solved and no black smoke on start-up. I need to change he engine mounts as there is still a bit of shake at idle.

Pick up from standstill is good but it tends to be a bit flatter at around 3k whereas OBD1 keeps pulling. Economy also seems to be improved, although the next few months will tell properly. Also, there is absolutely no worry of lifting off the throttle and worrying that it will cut out, the revs just gradually drop to idle.