MrMK2-VR6 2 Posted January 22, 2014 Report Share Posted January 22, 2014 Hi guys, I have a 1991 mk2 with a VR6 OBD2 lump in it, recently it doesn't seem as quick, sounds like it's going well but seems to take a long time to rev, possible misfire?? I have search high and low for a diagnostics port but can't find one anywhere so can only assume whoever did the conversion chopped it off so unfortunately no VAGCOM help! I don't know of any relatively local vr mechanics in the midlands and can't really afford to pay pricey labour costs to fault find as I could spend hundreds and get nowhere with bill and Ben at budget auto's lol any advice or directions to a decent mechanic with vr experience would be much appreciated. I have changed the plugs and oil and given a general service but has made no difference, help desperately needed! VR6Pete 1 Link to post Share on other sites
mattvr6 133 Posted January 22, 2014 Report Share Posted January 22, 2014 Could b ur airflow metre,does it splutter at all? Sent from my iPhone using Tapatalk Link to post Share on other sites
MrMK2-VR6 2 Posted January 22, 2014 Author Report Share Posted January 22, 2014 Has spluttered a few times on first start up but other than that no. Starts and drives no probs just struggles to keep up with regular traffic unless ur ragging it. Seems to take around 6 seconds to get from 2000 rpm to redline in second gear with full throttle which is a lot longer than usual, also the mpg starts at less than 10 when first started but once done a few miles go'a up to around 17 but never any higher, is the MAF the box on the air intake just after the filter before it joins the throttle body and if so is it possible to clean this? Would the lambda cause similar symptoms? Also there us an intermittent whistle from the engine bay when under acceleration, have checked for obvious leakage but can't see anything, is there a specific way of pressurising the intake system to check continuity if airflow? Also where might I find the ecu as I may then be able to find the diag port and get it plugged into VAGCOM Link to post Share on other sites
mattvr6 133 Posted January 23, 2014 Report Share Posted January 23, 2014 Ecu is under the scuttle panel mate, try disconneting the maf c if that makes a difference Also the coolant temp sensor could b at fault try that it's the blue one on the front of the engine under the coil pack theirs 3 in a row so to me it's over fueling Sent from my iPhone using Tapatalk VR6Pete 1 Link to post Share on other sites
MrMK2-VR6 2 Posted January 23, 2014 Author Report Share Posted January 23, 2014 theres only a blue and black one and a third is just a blanking plate, definately no ecu in skuttle so really baffled now, have ordered temp sensor so will see if that helps, any idea where the lambda sensor would be (exhaust manifold yes) but where? Ive searched and searched but no luck, thanks for replies fellas, will let u know if the CTS does the trick Link to post Share on other sites
MrMK2-VR6 2 Posted January 23, 2014 Author Report Share Posted January 23, 2014 definately over fuelling, smells strongly of fuel and MPG is worse than chieftan tank thinking of buying shares in BP Link to post Share on other sites
Lukey. 381 Posted January 23, 2014 Report Share Posted January 23, 2014 (edited) Lambda sensor is screwed ino the cat, what colour are your injectors? Is your exhaust sooted up to fook? Edited January 23, 2014 by Lukey. Link to post Share on other sites
MrMK2-VR6 2 Posted January 23, 2014 Author Report Share Posted January 23, 2014 not checked injectors but no smoke or soot from exhaust, it does have some noisy tappets but that wouldnt result in the power loss Link to post Share on other sites
mattvr6 133 Posted January 24, 2014 Report Share Posted January 24, 2014 Follow the loom back through the car then I'll find the ecu mate, I'd try a temp sensor mate and check vac pipes etc Sent from my iPhone using Tapatalk Link to post Share on other sites
GordonC 20 Posted January 24, 2014 Report Share Posted January 24, 2014 The ecu has probably been put in behind the glovebox. The diagnostics port should be below the heater control panel above the ashtray behind a rectangle blanking plate. It usualy just slides to the right mate if that helps anyVR6 Loonibuggy Santa Pod 2014 ! VR6Pete 1 Link to post Share on other sites
VR6Pete 1,455 Posted January 24, 2014 Report Share Posted January 24, 2014 Where in midlands are you? I'm from stoke and can probably help initially I'd say MAF or blue temp sensor Club Chairman Link to post Share on other sites
MrMK2-VR6 2 Posted January 25, 2014 Author Report Share Posted January 25, 2014 (edited) im in bromsgrove pete have ordered temp sensor, hoping that will do the trick as its so inexpensive, new MAF is 150+ so would idealy like it plugged into VAGCOM before spending that sort of cash if thats not the issue, today the car has started to splutter as if running out of fuel and cutting out every time i came to a stop and idling, this may point more towards the MAF tho so if no joy with temp sensor i will search for a used one Edited January 25, 2014 by MrMK2-VR6 Link to post Share on other sites
Lukey. 381 Posted January 26, 2014 Report Share Posted January 26, 2014 If you search for a maf it has to be the right kind there's 2. Hot wire and hot film, hot wire are cheaper and more available as they were used on more models, the hot film (which my OBD2 has) it looks like a microchip sticking out of the bottom and they were only for this engine, the 2 types are not interchangeable. So get the right one. Link to post Share on other sites
MrMK2-VR6 2 Posted January 26, 2014 Author Report Share Posted January 26, 2014 i have now found out that i have an OBD1 engine, this is confusing to me because i have coilpack?? I was told that OBD1 didnt have a coilpack, will check in the fusebox area for ecu and diag port, cheers Link to post Share on other sites
Lukey. 381 Posted January 26, 2014 Report Share Posted January 26, 2014 think some late on OBD1 have coilpacks Link to post Share on other sites
mattvr6 133 Posted January 26, 2014 Report Share Posted January 26, 2014 On the change over 94/5 ish can get late obd1s with coil packs till they all changed to obd2 with more power Sent from my iPhone using Tapatalk Link to post Share on other sites
MrMK2-VR6 2 Posted January 26, 2014 Author Report Share Posted January 26, 2014 ah ok that makes sense thanks, Link to post Share on other sites
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