Ian C Posted March 27, 2004 Share Posted March 27, 2004 Boy am I enjoying car ownership. So, car still isn't running right. However, I have got a stable condition out of it, and a few definites at last. Symptoms: *Car runs very rich all the time - checked on an emissions machine, it's 6 to 9+ % CO2 instead of 1% or so. OK, it's decatted but that's still a crazy amount. Idle, liftoff, acceleration, and closed loop. O2 sensor reads 0.95v all the time (i.e. it's screaming "I'm rich dammit!" at the ECU) *When you lift off and close the throttle, the injectors do not switch off. *The over-richness and the running of the injectors on liftoff cause chugging in gear and attempted stalling out of gear. Things that are OK/I have done: *ECU - ran Matt Harwoods car OK *All connections from footwell section of loom to the ECU, including the stock ECU plug in that loop - tested all 80ish of them with a probe and multimeter, so I finally fixed everything there without having to chop in a whole new loom section and ECU plug. Fixed a bad connection that I found to the aircon clutch. *Throttle position sensor - tried another one, checked readings, checked connections *O2 sensor - tried another one, checked readings, checked connections *Coolant temperature sensor - tried another one, checked readings, checked connections *Intake air temperate sensor - tried another one, checked readings, checked connections *MAP sensor - tried another one, checked readings, checked connections *Fuel pressure regulator - tried another one *Fuel rail - tried another one *Fuel pressure - 49psi static *Fuel return - 90lph *Idle Air controller - tried another one, responds to aircon and lights idle-up OK *I have desoldered and wholly removed all three piggyback units from my wiring loom - Fuel Cut Defender, Apexi AFC fuel computer, and Apexi AVCr boost controller. This, incidentally, resulted in a more consistent engine, so all the manipulating of the loom had obviously caused many problems Things measured at the fields harness: *MAP voltages read 1.5 to 1.6v at idle *O2 sensor builds up to 0.95v and then stays there at idle *IDL1 connection is 0.0v with a shut throttle and 11.6v with an open one, so the ECU is getting the "Hi, you've got Idle" signal. I'm fucking stumped. Why is it running too rich? Why isn't it killing the injectors on overrun? Why me? This is the crux of all my problems it seems. Bear in mind the last mods I did were cams way back before 10otb2 last year, so it's been peachy and then suddenly this. -Ian Quote Link to comment Share on other sites More sharing options...
Branners Posted March 27, 2004 Share Posted March 27, 2004 What alarm system is on the car? I have seen some strange problems come from failing immobilisers.. JB Quote Link to comment Share on other sites More sharing options...
Syed Shah Posted March 27, 2004 Share Posted March 27, 2004 When you say you ran Matt's ECU and car was ok, does that mean your ECU is what is causing the problem? Is it stock or aftermarket? Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 27, 2004 Author Share Posted March 27, 2004 Autowatch alarm of some sort. Syed - my ECU ran *Matt's car* OK, as in we installed it in his and it ran fine. Couldn't try his in mine as it wouldn't even start at that point thanks to all the dodgy (and now theoretically fixed) problems at the ECU plug. I've gotta find the speed delimiter and see what that's all about, but after that, hmm, I can only think of one next step, and that's gonna need some serious favourage off this BBS - If I made a list of pins/wires to check, someone else gets their car to a warm idle and checks the voltage on those wires as close to the ECU as possible, and posts it up here so I can compare what my ECU is seeing with what their ECU is seeing. It's a shit job as it's messing about in the footwell, and you'll need an insulation-piercing probe to do it, but the more people who do it the merrier and it would be a fantastic resource for the future. Any volunteers...? I can get the pins to check listed tomorrow... -Ian Quote Link to comment Share on other sites More sharing options...
Syed Shah Posted March 27, 2004 Share Posted March 27, 2004 Ok, so what non-stock stuff is connected to the car at all at the moment? Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 27, 2004 Author Share Posted March 27, 2004 Greddy turbo timer Some sort of speed limit defender somewhere (I think it's a Pete betts one) Autowatch alarm Anything else is pretty much standalone, like the EGT and boost gauge. -Ian Quote Link to comment Share on other sites More sharing options...
Syed Shah Posted March 27, 2004 Share Posted March 27, 2004 All three of them working fine? Regardless, I would remove them, and put it all back to stock, a lot of hassle, but isolates many of the potential trouble makers. Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted March 27, 2004 Share Posted March 27, 2004 I'm more than happy to measure any voltages anywhere for a comparison. I can't see that a dodgy speed converter could cause any problems, but worth taking out the loop, just in case. You should only have 1 wire going to the ECU, and if it's there, it will be a cut wire with the car side disconnected. Just reconnect the two and it sould be normal again, with a 112mph limiter The converter itself, will almost certainly be behind the dash cluster. I assume you're happy with the ECU plug at the moment? Quote Link to comment Share on other sites More sharing options...
Branners Posted March 27, 2004 Share Posted March 27, 2004 Matt, do you know the alarm system and how it does its immobilisation on the car? I saw a Clifford sit there and keep the fuel pumps on a car running once because the immob was messing about. JB Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted March 27, 2004 Share Posted March 27, 2004 When I was with Ian, I didn't think to check the alarm. But, if it is the alarm, the person that fitted it would need shooting as its clearly not an immobilsation point that's being cut. In honesty, I doubt the alarm could cause the problem Ian's having... Maybe something else to bypass, just to be safe Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 28, 2004 Author Share Posted March 28, 2004 Here is a word doc with the pins to check, at a fully-warmed-up idle: -Ian PS the cells marked in red are the ones I'd like you to check - as many people as possible please If anyone wants the original doc with the pinouts on let me know and I'll post it.pins to check.zip Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 29, 2004 Author Share Posted March 29, 2004 After much diagnosis and so forth with the assistance of Mr Blake, we've come to a tentative conclusion that the ECU is seeing the right O2 values but is ignoring them - as in, it's constantly in open loop mode. Any ECU experts out there know what makes the ECU switch to open loop and also back to closed loop? Looking forward to your voltage measurements too folks Help me out, it's getting summerier out there... -Ian Quote Link to comment Share on other sites More sharing options...
Adam W Posted March 31, 2004 Share Posted March 31, 2004 Open loop vs closed loop should be dependant on thorttle position and engine load (ie MAP sensor), I'm sure you knew of those two already, but I can't think of anything else. Coolant temperature perhaps? Quote Link to comment Share on other sites More sharing options...
eyefi Posted March 31, 2004 Share Posted March 31, 2004 have u done the vac test on IDL1? Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 31, 2004 Author Share Posted March 31, 2004 Originally posted by eyefi have u done the vac test on IDL1? WTF is the throttle opener? Pictures please -Ian Quote Link to comment Share on other sites More sharing options...
Digsy Posted March 31, 2004 Share Posted March 31, 2004 Is it that cylinder thing on the passenger side of the throttle body that doesn't apear to be conected to anything? I thouhg tit was a dampener or something... Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 31, 2004 Author Share Posted March 31, 2004 I thouhg tit was as well I put a long hose on it today and sucked, blew etc at idle, made jack shit difference, and only had a very slight suction on it with a more open throttle. I could blow through it OK with the engine off so it's not got a blockage in the throttle body from what I could tell, so I've still no idea what that bit is for... I put a set of 440cc injectors in it last night, and got to fire it up properly this evening. I got a) an O2 reading that wasn't constantly off the clock b) an O2 reading the fluctuated up and down like it was in closed loop mode, and c) a nasty missing engine as one or more of the injectors wasn't performing properly - as they had sat in a non-sealed plastic bag for nearly two years in the garage I'm not suprised. Also when I revved up it went rich, and if I held it it paused and went back into closed loop mode. Of course, it could have been the missing injector causing the drops in O2 voltage but I don't think so. Oh, and, despite the missing, I could rev up and let go as much as I wanted but every single time it dropped to the right idle speed, never below, not like I've been experiencing. I put the 550's back in tonight, and it behaves exactly as it has been the past couple of months Revving up and holding doesn't change the O2 reading, so it still can't reach stoich even at 3000rpm (not under load though) So - theory now is - it's overfuelling (duh) to a point where the ECU runs out of adjustment to bring the fuelling down via the O2 sensor with 550cc injectors, but can do it with 440's. This overfuelling causes all my symptoms of poor cold start, idle, and overrun-idle transition As to why it's doing this, I don't know. I want to check the fuel pressure again, and maybe the flow back from the fuel rail. If there was a blockage in the return the fuel pressure would be off the clock and would cause exactly what I'm seeing here. Hmmm. I know that when I installed the 550's originally it ran OK. I know also that a lot of other people have installed 550's and they have run, unmapped, OK as well. So something is artificially increasing my fuelling, either a fuel map modifier gone postal or very high fuel pressure. -Ian Quote Link to comment Share on other sites More sharing options...
Dragonball Posted March 31, 2004 Share Posted March 31, 2004 I assume that you disconnected the resistor pack to repalce the 440's Perhaps this boy is faulty - not earthing etc? Could this effect the running of the 550's? Quote Link to comment Share on other sites More sharing options...
Digsy Posted April 1, 2004 Share Posted April 1, 2004 I suggested that the resistor pack may be faulty but Ian reckons he's measured the resistance and its ok. Good to hear you are making some progress dude! Quote Link to comment Share on other sites More sharing options...
Dragonball Posted April 1, 2004 Share Posted April 1, 2004 Originally posted by Darren Blake I suggested that the resistor pack may be faulty but Ian reckons he's measured the resistance and its ok. Good to hear you are making some progress dude! Hve a word with Emin - he can probably knock you up ew one (resistor pack that is) quite quickly - and still sell one on after if OK:thumbs: His are only £50 now Quote Link to comment Share on other sites More sharing options...
Ian C Posted April 1, 2004 Author Share Posted April 1, 2004 Resistor pack is giving a steady 8 ohms on each pin out. It hasn't actually got an earth point I did a nice bit of bypass wiring when I put in the 440's. Takes about an hour to swap the injectors now Quote Link to comment Share on other sites More sharing options...
eyefi Posted April 1, 2004 Share Posted April 1, 2004 do u think one or more of the 550's r sticking open? Quote Link to comment Share on other sites More sharing options...
eyefi Posted April 1, 2004 Share Posted April 1, 2004 Originally posted by Ian C I thouhg tit was as well I put a long hose on it today and sucked, blew etc at idle, made jack shit difference, and only had a very slight suction on it with a more open throttle. I could blow through it OK with the engine off so it's not got a blockage in the throttle body from what I could tell, so I've still no idea what that bit is for... i think its meant to b tested at ign on and measure the voltage with vac applied, probably need to use a syringe, unless yr a really good sucker but it sounds like yr getting somewhere. Quote Link to comment Share on other sites More sharing options...
Ian C Posted April 1, 2004 Author Share Posted April 1, 2004 All the plugs looked exactly the same regarding blackness and wetness every time I've taken them out so I think the problem is across all six cylinders evenly, plus if it was just one injector the others would be pulled down to a lean state to compensate for the richness produced by one of them and that would be a noticeable engine condition I reckon. Do you reckon that daft little pipe by the TPS with the check valve in it could have something to do with idle control and all that then? I'll have to have a look at another Soop to see how that one behaves... Actually, if people can fit it in around checking their ECU voltages for me , can they see if they get any noticeable vac/pressure around that load of hoses? -Ian Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 1, 2004 Share Posted April 1, 2004 Glad the injector idea worked out Ian. I have never seen a J-Spec on bigger injectors without ecu kludging that runs right myself. Why should it? It needs remapping, the O2 sensor will only try and trim an existing hard map. Maybe the ecu has some inbuilt stuff that sends it into limp home mode if the O2 sensor tries to trim outside a set parameter. have you tried a new O2 sensor? I am not advising you run big injectors with a stock ecu, just wodering why it worked initially, but not now... Maybe you should ring me in the pub more often, my most creative ideas seem to hatch in there Maybe send beer money And I WAS impressed by the speed of the injector swap, it took all of what, err 4 / 5 pints long! Quote Link to comment Share on other sites More sharing options...
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