RobH

A note about Venom injectors for anyone searching threads! Venom injectors are reknowned for having differing flow rates across a supposed 'matched set' - this would not cause all 6 injectors to run over rich regardless of what injection multiplier I run. Another historic issue which gave them 'bad press' was that the seals supplied with them were cr*ppy, this issue has been resolved so whilst they may not be perfect they are not causing my current issue. My experience has not been great, one of the set I purchased was stuck open and caused a hydraulic lock, I eventually got it replaced after a delay of around 2 months. I'm now under the impression that Venom may actually remanufacture injectors as reference was made to 'cores' being available for my replacement part. Another observation was that if the set is actually flow matched, Venom (Python injection) would have noticed that one was stuck open. In retrospect I would not have chosen these injectors but that's not to say I could have been lucky and had no problems at all and saved myself £300 on a set of Nismos. Some people have had issues with one particular guy who sells these, I suspect they approached him with an aggressive attitude and he didn't respond well, he was helpful enough to me. John, the Nistune software and product is excellent, I'm sure the fault lies elsewhere. Pete programmed it with what he thought would be a good base image for my setup. K constant was 193 - this is what the resize injectors feature calculates and should be roughly correct. I've experimented with a few different maps, starting with a very basic standard map and changing only the K constant (and related TP and TTP scales), the best results I've had at idle were a K constant of 70-100 (!). I've tried K constant of 193 and tweaked the Latency from the 1500 micro seconds default right down to zero, Venom suggest starting at around 700 and to be fair it does run a little better (but still awful) at 700. It's not running well enough to rev much above idle as it is, if I make it idle by using a low K value it will barely rev above that at all...from the evidence so far, it's extremely rich across the entire range. I haven't checked the fuel pressure as yet, my mate also suggested this - are you thinking perhaps the pressure regulator is shot? Temp sensor is ok afaik, is the consult reading the gauge temperatue or the ECU temperature? Cheers H

Hesitate to say it, Venom... Don't see this makes a difference though as all cylinders are running equally as over rich... One further point, I unplugged the MAS earlier this eve and it actually idled a lot better. The revs seem to bounce between about 1200 and 300 in 5 second cycles, min revs seem to drop further and further and it will eventually stall.

Hi all, Any suggestions for the above? I've been testing after being off the road for a couple of years. Previously untested mods are 550cc injectors, FMIC, straight through exhaust, AIVs gone, EGR gone, carbon can gone, aircon gone, plenum water bypass, stock boost solenoids gone, std recircs gone, Nistune daughterboard ECU management (set up roughly correct for 550cc injectors). Other stuff I've been running for a while, Blitz BOVs, AVC-r, intake, decat exhaust, SE chip (prior to Nistune). I have to lean the injectors out to approx 1/3 of what they should be running at to make it idle, I still get black smoke and sooty plugs. Hardly any power at any injector setting. Whilst I know I have a lot of adjustment to do to the fuel and ignition maps to make it fulfil it's potential, it's running far too poorly with what should be a reasonable base setting for it to be a problem with the ECU program. Changing settings in the ECU isn't really making much difference at this stage therefore I have to assume I've made a b*lls up elsewhere. I'm running an AVC-r, stock boost solenoids and their pipework have gone, just wondering if a problem with this may cause wastegates to stick open thereby richening the mix when it comes onto boost (?) So far I can only think it might be a MAF sensor problem (reading around 1.5V at idle - think this is ok(?)), a massive boost leak allowing all the air to escape after it's been metered or possibly a badly routed vacuum line having a similar effect, maybe crappy injectors or seals (doubtful as all plugs are equally black). Any suggestions greatly appreciated, I suspect I may be approaching the issue a bit narrowmindedly - I could have missed something which is galringly obvious to someone else... Cheers RobH

OK I'm pretty sure 0.3 or thereabouts is a duff sensor - unplugging from the loom gives this reading on both sides. I've got a spare pair anyway, I'll bung 'em in and see what happens, was hoping to avoid doing this now the engine is back in, looks a bit of a nightmare :-(

this is quite the opposite of what is posted here http://www.twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=2123769&forum=general&dtSearch=0 I'm sure I read elsewhere that 0.3V was dead too...I'll keep looking

Hmm...I'm sure I'd read somewhere that approx 0.3 meant it was a dead 'un...

Hi all, I'm pretty sure I have a dead O2 sensor but not quite sure whether they're both shot. Using datascan, RHS reads 0.30 - 0.32 and hardly changes, LHS drops progressively as the engine warms up (!?), starts at around 0.33 and after 5 minutes or so is reading 0.06 - 0.10, occasionally goes up a bit by blipping the throttle. Are either of these exhibiting normal behaviour?? Out of interest these are Bosch sensors and have a different sized hex to the standard NGK ones. Cheers RobH

Hi all, Just wondering if anyone has any advice as to how to secure the stock front bumper when using a front mount intercooler (i.e. side mounts and ducts have been removed). I've bolted it back on with what mounts are still available but it's a bit 'flappy' at the sides - just in front of the wheels. Suppose the same applies to aftermarket bumpers too. Not sure if it would self destruct if I used it as is... Cheers RobH

That's a different debate entirely ;-) BUT as your recircs are currently redundant anyway (or should be if the BOVs are working correctly) you're not going to notice any difference if you remove the recircs and plug up the holes properly. What have you guys used to plug up the 'stubs'? I've currently got rubber chair leg covers held on with hose clips :O). If someone made these in silicon they'd be ideal - as it is they fatigue within a couple of years and need replacing. Think the 'norm' is to use silicon hose with metal bungs... Cheers H

Thanks guys, I tried Houghtons last week and they didn't want to know (!?). Carole Nash are due to call back. I'll give the rest a try tomorrow. Best I've had so far is Adrian Flux, who insured me a few years ago, not too bad at £539. Cheers H

Hi folks, I'm looking to renew my insurance after 2 years off the road. Most of the companies mentioned on here seem to be dead ends for me 'can't quote you sir' or crazy money. I don't get it...my details are as follows: 38 years old 5 years NCB 1990 Jap TT manual Second vehicle, no more than 5K miles per year Value - virtually nil! Parked on private driveway. Cat 1 alarm/immob Mods: 550cc injectors AVC-r Exhaust Intake FMIC hybrid tubs NISTune programmable ECU daughterboard (chip) Nothing extreme by any means! If any of you have similar mods and reasonable insurance, I'd be most grateful if you could advise of the company and particularly if you can quote me a reference number that I can quote back at them when they say they can't quote! Cheers RobH

Ok, I've had the suspect injector tested by Direct Diesel of Chester, a bit expensive in my opinion but at least it got the job done! Injector has tested as being stuck open!! I feel a warranty claim coming on. Cheers for all the help and advice guys - much appreciated. H

Apparently Direct Diesel in Chester can fit ZX injectors on their bench, I'll get it checked out on Monday. Have done the click test and it seems to be ok. Didn't work quite how I expected it to though. When rotating the CAS shaft, injectors only click when I stop turning the shaft (!?) Is this correct? I can't run the engine as it is so can't do the 'dynamic' click test. Cheers H

Bit of a dead end Andy, but thanks. The guy on the other end of the phone didn't seem to know what a fuel injector was - much less where to get one checked... Apparently Bal Muir in Wrexham (01978 856412 for reference) is able to test injectors but nobody's picking up at the moment. Think the 'click test' is the most obvious route. Do the injectors normally operate at 12V? If so, is there any issue applying 12V directly to the terminals from the battery to check operation? Cheers H

OK, I've pulled the injector, BTW wouldn't recommend the Dremel method for anything more than 1 injector! From what I can see there was no problem with the seals, lower seal remained in the plenum but appears to be undamaged. Whether it popeed straight when the injector came out I can't tell :-\ I now need to confirm whether the injector is permanently open, any suggestions how to best accomplish this? (CAS click test?). Do garages generally have facilities for testing injectors or do they have to go to a specialist? Cheers H

Thanks to both. I thought the car was running ok, but have replaced the rear pipes, the new pipes are much frutier so I couldn't tell if it was a different note due to pipes or running on 5. Seems it's been running on 5 (at best) since I got it going. I've tested the resistance of the suspect injector directly and via the loom at the ECU, that seems ok, not sure if this would identify a stuck injector but at least it rules out the wiring. I'll leave the ECU as the last possibility, I'm about to dremel and remove the possible culprit, expecting a kinked o-ring. Cheers H

LMAO - noid lights, you're making this up Andy!! No, seriously, looks like a good idea but I seem to be overspending on 'single use' tools at the moment, another one for box at the back of the shed :-\, s'pose it's only £15 but they all add up. Don't s'pose anyone in the Chester area has a set I could borrow?? Couldn't I just rig an appropriate bulb and wires to the suspect injector and get the same result? I don't suppose these Draper items would fit our connectors 'out of the box' anyway...? Cheers H

Yes, I've put up a post about it. I took plenty of care and grease when fitting. Seems most likely it will be an O ring though. I put up another post earlier today specifically about this. Looks like I need a new Dremel as I'm not pulling the plenum again just for 1 injector :-( Cheers H

Hi guys, following my problems yesterday which I attributed to a knakd starter it appears my problem is actually a hydro (hydra? - surely hydro would be water? - never mind!) lock in one cylinder. The general view seems to be either a stuck open injector or more likely a pinched lower injector o-ring. I have recently upgraded the injectors so I guess the O-ring would be the place to start. Any observations or other possibilities? Cheers RobH

Hi Mark, did you manage to sort this problem out? It sounds like I have a similar prob. Must be something they put in the fuel in Chester ;-) Cheers RobH

Hi Mr D. No, the ECU is ok, I pulled it out a few days ago to install a NISTune daughterboard, all looked fine. Currently running a stock map with modified K constant to allow for bigger injectors - otherwise standard. Are you suggesting that there is a different circuit for each injector? I'm only getting this problem in #6 cylinder although if memory serves me correctly this is the first cylinder on the fuel rail... Cheers H

UPDATE!!! Rich came round this eve and we persevered with turning the crank - up to a point. Crank eventually 'locked' and pulling all the plugs revealed the pass side rear cylinder was indeed hydro locked!! Sorry to have doubted you Giant Slayer ;-). Dried it out and it started, BUT subsequently trying to start again the same thing happened again. So, it looks as though number 6 cylinder has an injection problem, not something I know a lot about. Is it possible to test the injector in situ? I suspect it's stuck open (if this is possible) and is flooding the cylinder. nellys300zx, thanks for your help , part number is no longer needed - hope you see this before going to any more trouble. Thanks for your help so far! H

Thanks guys, I'm keeping my fingers crossed for a battery recharge but think I'm kidding myself. I've priced up a Blueprint starter but they want £150 odd - trade!! If anyone has a Mitsubishi or similar part number I could use to cross reference it would be much appreciated. I've found one listed for 1983 - 1994 (?!) which suggests the Z31 used the same starter, I would expect later model Z32s to also use the same part so something looks a bit fishy there...anyone know if this is true or false? Also, is there a resistance test I can do on my starter? Cheers H

Battery is on charge just to rule that one out. I did consider a fluid lock as it was overfuelling when it last ran, I pulled a single plug earlier, which was bone dry. Having turned the crank by hand though I can confirm that it's turning as freely as it ever did so a lock is unlikely. Thanks for the suggestions, keep 'em coming ;-) H

yeah, it is a conversion job but if it was a switching prob I'd expect no action at all when turning the key. As it is it 'heaves' (makes a noise like it's trying) and then falls silent despite still being under heavy load. Think of it like a weightlifter who gasps on the initial push and then holds his breath whilst holding the weights up - still under strain but no further sound ;-) Cheersssssss!