radio_nasty 0 Posted June 6, 2017 Report Share Posted June 6, 2017 Hey folks... I'm new to this forum, but was hoping for a little help.I recently swapped an OBDI 12V VR6 into my 1999 Mk3 Jetta (OBDII, obviously), but I'm keeping the engine OBDI.I converted the VR6 from a dizzy to a coilpack.The engine will start, idle for a few seconds, then die. Strong gas smell, I've even had raw gas coming out of the exhaust.I've checked all my connections, the fuel pressure regulator, IAC valve, TPS, etc. Seem to be correct... I've plugged and unplugged these in a hundred different combinations, but I seem to get the same result no matter what's plugged in or capped off, etc. It certainly doesnt seem to be a vacuum issue. Any ideas?Thanks in advance for your help... This thing is making me crazy. Link to post Share on other sites
Timothy_Ellis 23 Posted June 6, 2017 Report Share Posted June 6, 2017 Take it back to dizzy and try it. Link to post Share on other sites
radio_nasty 0 Posted June 6, 2017 Author Report Share Posted June 6, 2017 Take it back to dizzy and try it. I could try that... Also the ECU and wiring harness that I have are from an engine that had a coilpack. Will that make a difference? Link to post Share on other sites
Timothy_Ellis 23 Posted June 6, 2017 Report Share Posted June 6, 2017 Not entirely sure, do you still have all original equipment for the dizzy setup? It could be in the ecu. Link to post Share on other sites
radio_nasty 0 Posted June 6, 2017 Author Report Share Posted June 6, 2017 I do still have everything for the dizzy, except the ECU.So thats part of the problem, I would need another ECU (I think)This engine has the block and head from a late '95 VR6 with the dizzy and no EGR, and the ECU and wiring harness from an early '95 VR6 with a coilpack and EGR, hence the dizzy to coilpack conversion. Link to post Share on other sites
radio_nasty 0 Posted June 8, 2017 Author Report Share Posted June 8, 2017 Update:I pulled the fuel rail and found that the return line was completely clogged... Cleaned it out, and now the engine will run and sounds fine, HOWEVER:I'm still running rich and fouling 4 of the 6 plugs... Still getting raw gas coming out of the exhaust. Any ideas? Bad fuel injectors? Link to post Share on other sites
Timothy_Ellis 23 Posted June 8, 2017 Report Share Posted June 8, 2017 Fuel pressure regulator? Link to post Share on other sites
RBPE 198 Posted June 9, 2017 Report Share Posted June 9, 2017 (edited) Speaking on later ME7 stuff, there are times calculated to charge the coil and release the spark ensuring a proper burn, sometimes people get lucky in that they'll get deflagration over detonation as the times are similar, upgraded coils have a better energy/enough for proper burn based on the oem map times etc, but you always want to be running the set times for said coils - so use the ecu that uses those coils or the maps at least! If you're changing these then 1st port of call is always to sort the map out first or you're risking trouble - so if you're not sparking the mixture properly in time, like this vid, then I wouldn't risk running it until sorted! You can see the way the mixtures are igniting or not or fuel just getting washed out with no combustion etc here; https://en.wikipedia.org/wiki/Deflagration_to_detonation_transition I haven't got access to my 12v files at the moment due to hard drive problems, but I'll see if I can dig out the differences if I have time, you can see how many ignition maps there are in this VR6 12V and why the timing is very important; Edited June 11, 2017 by RBPE Link to post Share on other sites
RBPE 198 Posted June 9, 2017 Report Share Posted June 9, 2017 (edited) P.S. AGR is EGR above so there can be further changes needed for EGR delete for example on the same ecu, it has been some years since I played with the older Motronic, but above is very much likely the answer without being able to put the 2 variant ecu's together! Time's are ms which is very finite so getting that spot on is essential and the maps shown above don't even show the after-start and warm-up changes, so lot's are dependent on the ignition maps being right. You can see on the vid that when they aren't the fuel can do all sorts and wash out the port without any ignition if too far off. Edited June 9, 2017 by RBPE Link to post Share on other sites
radio_nasty 0 Posted June 9, 2017 Author Report Share Posted June 9, 2017 Thanks for the input.However, like I said earlier, the only parts of this engine that arent from the same car are the block and head... So shouldn't the ECU already be set to work with the coil and all of the other ignition components present?If not, how would I even go about mapping/adjusting the computer? That is something I've never gotten into. Thanks again. Link to post Share on other sites
RBPE 198 Posted June 9, 2017 Report Share Posted June 9, 2017 What?..... "I recently swapped an OBDI 12V VR6 into my 1999 Mk3 Jetta (OBDII, obviously), but I'm keeping the engine OBDI. I do still have everything for the dizzy, except the ECU.So thats part of the problem, I would need another ECU (I think)This engine has the block and head from a late '95 VR6 with the dizzy and no EGR, and the ECU and wiring harness from an early '95 VR6 with a coilpack and EGR, hence the dizzy to coilpack convesion" Link to post Share on other sites
radio_nasty 0 Posted June 9, 2017 Author Report Share Posted June 9, 2017 Basically, I bought a vr6 from a 95 golf It came with a distributor, but it apparently had no EGR from the factory... The port coming off the TB for the EGR was absent, so it hadn't been deleted. (My Bentley manual says that some 1995s didnt have EGRs, others did.) Anyway I couldnt obtain the ECU for this engine. Later I got a crazy good deal on a rusty Jetta GLX parts car, also a 1995... (It DID have an EGR, but had a coilpack instead of the dizzy) So I had to use the ECU from this junk Jetta. Since I was stuck using the ECU from a coilpack engine I converted the Golf engine to use the coilpack, thinking it wouldnt work properly with a distributor (according to VW vortex) and thats the setup I'm trying to run now. Hope this makes sense. Link to post Share on other sites
RBPE 198 Posted June 11, 2017 Report Share Posted June 11, 2017 Ah, right, got ya! It's been a while since I've done anything on the older cars or ecu's so you'll have to do the working out and look into the info but in terms of the various engine swaps and ecu tuning I do I tend to take this approach; Firstly - obviously check things like injector seals, wiring, is the maf in good nick, no tight bends before it causing turbulent flow for readings, fuel pump in good nick, fpr etc - things like that - basically knowing that your air/fuel/sensor parts work fine/the hardware side is all up to scratch - preferably with as much to oem for that ecu that people can afford or you can set up. Then - is everything else the same between the models/engine's - are the injector flow rates the same, is the fuel pressure the same, do you have vvt variances for example which means the ignition timing maps are a little different to a none vvt one and so on. Main problem is that there were a lot of quick changes in the 90's as legislations came in for emissions, you can get things like EGR and non EGR in the same year like you said - so next bit is checking that the parts did not vary too much, if the ecu is set up for an EGR 200cc injector and a non EGR one was 185cc's for example, then that can cause problems as well as, in this case, not having certain things for the maps like EGR.... all add's up. If that's all sorted then yes, it is likely to be the EGR variances as you can see in the screenshot above they are a part of ignition. Most people should probably do that if they use a certain mapper, like a local one you always use or one's who do lot's of cars or aren't particularly knowledgeable on model variances, you can help save them time pinpointing things that are different and need looking into in that respect. Hope that helps Link to post Share on other sites
radio_nasty 0 Posted June 11, 2017 Author Report Share Posted June 11, 2017 I think I'm going to have to hit the junkyard and find another ECU, maybe swap it back to the original distributor setup... I had no idea about the different injectors for EGR vs non-EGR, maybe that's part of my problem too?!? I really appreciate you taking the time to provide detailed information, cheers. Link to post Share on other sites
RBPE 198 Posted June 11, 2017 Report Share Posted June 11, 2017 Just now, radio_nasty said: I think I'm going to have to hit the junkyard and find another ECU, maybe swap it back to the original distributor setup... I had no idea about the different injectors for EGR vs non-EGR, maybe that's part of my problem too?!? I really appreciate you taking the time to provide detailed information, cheers. No - I'm not saying there ARE any differences between injector flow rates, I'm saying you SHOULD know if there are any differences - it could literally only need an EGR code out to sort - I'm just saying I'm rusty on these older ones and didn't do much with them anyway but all conversions or engine/ecu changes people need to be aware of these things or there could be more that can cause problems in this instance than just the EGR variance - covering all bases! Link to post Share on other sites
radio_nasty 0 Posted June 11, 2017 Author Report Share Posted June 11, 2017 2 hours ago, RBPE said: No - I'm not saying there ARE any differences between injector flow rates, I'm saying you SHOULD know if there are any differences - it could literally only need an EGR code out to sort - I'm just saying I'm rusty on these older ones and didn't do much with them anyway but all conversions or engine/ecu changes people need to be aware of these things or there could be more that can cause problems in this instance than just the EGR variance - covering all bases! I see. Makes sense... I just talked to a guy (who runs a VW specialty shop) coming out to look at it this week, hopefully he can help narrow it down and save me some time. Link to post Share on other sites
radio_nasty 0 Posted June 20, 2017 Author Report Share Posted June 20, 2017 Ok, so I had my VW guy take a look at it... He told me its probably an injector sticking open with a fault somewhere in the wiring harness. I pulled the blink codes and got an "injector #3" code, so today I'm gonna pull the intake manifold and check the harness. He also said it sounds like the timing might be off too, so I may as well pull the valve cover and check while I have it apart. I'll follow up once I get it put back together... Link to post Share on other sites
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