TeKK Posted May 4, 2011 Share Posted May 4, 2011 Hello chaps, Lately, starting my 1.4K Supersport, the idle is fine and the car doesn't stall, but if I try and pull away, the car suddenly struggles loses all revs and almost cuts out. It's like I've dropped the clutch with no revs and it feels quite sluggish until it's been down the road a couple of times. Another way of describing it is like when you see a learner bunny hopping down the road without enough revs hehe Now I'm going to replace the spark plugs as a precaution (she needs them anyway) but could it be anything else? (am I just being too quick to drive off without her warming up?) Other than that she runs fine.. but that brings me onto... I was driving along the other day doing 60, coming to a 30 limit. I began to slow down and declutched to shift down to 4th. When I declutched, the revs immediately dropped well below 1000rpm and the engine cut out. Rolled to the side, started again no problem and hasn't done it again. She's only ever done this once or twice before and I think it was going down a slight incline, any ideas, should I be concerned? Link to comment Share on other sites More sharing options...
Englishmaninwales Posted May 4, 2011 Share Posted May 4, 2011 Try resetting the ECU Link to comment Share on other sites More sharing options...
Sheds Moderator Posted May 4, 2011 Share Posted May 4, 2011 Have you got an FIA red key? These things will ofetn cause rough running and cutting out, it did on mine. I took it for testing to a motorsport specialist, he went straight to it and diagnosed the fault. Link to comment Share on other sites More sharing options...
TeKK Posted May 5, 2011 Author Share Posted May 5, 2011 I do indeed have the red key on the side, could it be that general grime has got inside and fouled the contacts? I'll have a quick search for the process to reset the ECU if no one posts it here first Link to comment Share on other sites More sharing options...
Sheds Moderator Posted May 5, 2011 Share Posted May 5, 2011 Something like or corrosion on the contacts. They are pretty cheaply made and exposed to rain. The mechanic who did mine said that whenever they get a car in with rough running and one that's been there over a year they just replace it, they cost about £15. 9n times out of 10 it solves the problem and it's a quick thing to try. Some racers bin them every year as a matter of course. Link to comment Share on other sites More sharing options...
Mort Posted May 5, 2011 Share Posted May 5, 2011 I had something similar happen in my previous SuperSprint. Eventually tracked it down to being a string of silicone sealant that was floating around in the fuel tank - no idea how it got there, but I assume it was from contaminated fuel. When you applied revs it would be sucked to the fuel pipe and cause a cut out, but you could restart and idle fine, and even apply revs gradually and all would seem well. It might be worth running the fuel down and having a good look in the tank. Link to comment Share on other sites More sharing options...
TeKK Posted May 8, 2011 Author Share Posted May 8, 2011 Update Whipped off the distributor cap to find it in a sorry state, each contact had some heavy corrosion on the point at which the rotor gets closest and the rotor itself didn't look too healthy either. I've replaced the cap, rotor and spark plugs (spark plugs looked a bit dirty nothing major) and she started and pulled away ok after sitting for a couple of minutes. Will have to give her a run out and check (any old excuse eh?) Link to comment Share on other sites More sharing options...
TeKK Posted May 11, 2011 Author Share Posted May 11, 2011 Another update! Went to the meet last night and she developed a misfire on the way, only a couple of times. But returning home, it was a LOT more apparent. Thanks to some diligent searching of tech talk, the symptoms point a lot towards the TPS (Throttle Position Sensor or Potentionenementmenmeter) and the problems that come with it. Symptoms Hunting at idle, hesitation and shunting at light throttle pedal usage, fine if you cane it. However with all my searching I appear to have stuck in the wrong spark plugs. I've used BKR6E, when according to many threads I should be using BCP7ES (or BCPR7ES if I can find them), even tho the NGK site says the former. Would using these BK plugs also be affecting it in some way? Am going to attack the TPS tonight and will also check the IACV. Incidentally car is:1.4 K-Series Supersport with forward facing intake and distributor. Edited by - TeKK on 11 May 2011 13:24:48 Link to comment Share on other sites More sharing options...
Allen Payne Posted May 11, 2011 Share Posted May 11, 2011 I don't believe that the spark plugs would cause the intermittent misfire you're seeing, the TPS could but also check that the HT supply from the coil is not near the feed from the crank sensor and causing interference. Link to comment Share on other sites More sharing options...
jingars Posted May 11, 2011 Share Posted May 11, 2011 TeKK, I have been having very similar problems to yours; mine is a 1996 1.4 EU2 on a MEMS with forward facing plenum that has been re-built as a 1.8. I have swapped TPS and fuel pump, with no benefit. I swapped out dizzy cap and rotor arm, and noticed that the lead from coil to dizzy cap was blackened at the dizzy end (interior contacts of cap all seemed fine). I have swapped out the coil to distrubutor HT lead and although I have put less than 200 miles on since the change, it has not played up since. At £4.25 delivered from ebay (provided you don't mind a colour mis-match) it is worth a go! I am off on a little Euro jaunt at then end of the month, so I really hope I have mine sorted. If you find a definitive cause, please let us know I have purchased a new crank sensor to try, but haven't got round to fitting it yet; it is a real b'stard to get to... Link to comment Share on other sites More sharing options...
TeKK Posted May 12, 2011 Author Share Posted May 12, 2011 After further poking around the engine bay: My supersport has the old system of the solenoid operating the throttle when cold (so the choke) I have the old JZX 2963 throttle position sensor. I just took her out for a run, she was fine and dandy (I actually thought it was cured) until she was very hot, then the misfire returned. Foot to the floor, no misfire, all pointing towards the TPS as described above. Can someone please advise on the following: Where to find a replacement JZX 2963? (the current ones do not fit my intake, JZX uses brass arm connected to plenum to turn) or please advise if the newer ones can be made to fit? This all started happening after changing spark plugs, dizzy cap and rotor. Was fine beforehand. Would incorrect torque on the plugs cause this? The HT leads all seem fine and like I say, she runs fine until she's hot. Am starting to get frustrated with it now ☹️ Link to comment Share on other sites More sharing options...
Petrolhead Posted May 12, 2011 Share Posted May 12, 2011 How hot is very hot? Link to comment Share on other sites More sharing options...
TeKK Posted May 13, 2011 Author Share Posted May 13, 2011 Temp gauge is reading between 80-90 and oil pressure is at 4. So when I say very hot, I mean at a nice running temperature. This was after about 15 minutes of driving, with a stint of revving up to 4-5000rpm Link to comment Share on other sites More sharing options...
Englishmaninwales Posted May 13, 2011 Share Posted May 13, 2011 My 1400ss played up after I looped and cable tied the unused lambda probe wire spur to the engine loom. All sorts of erratic running problems. I guess it was getting an induced voltage which the ECU was seeing. Cured after I unclipped it. As above, I suggest resetting the ECU. Another problem has been arcing in the HT king lead connection at the coil. Link to comment Share on other sites More sharing options...
TeKK Posted May 13, 2011 Author Share Posted May 13, 2011 How can I spot the lambda probe wire? If it's unused can I just remove it? Also, what is the correct method for resetting the ECU? Is it: "Ignition to point 2, open throttle 5 times, ignition off" Am going to check the HT lead to the coil and the various other wires to the cool, plus remove the new dizzy and inspect that. Link to comment Share on other sites More sharing options...
Sheds Moderator Posted May 13, 2011 Share Posted May 13, 2011 Stop messing about, take it for a Krypton tune/diagnostic. Sometimes you can waste hours titting about and it's time to get the proper diagnostic tools on it. If you have done the obvious stuff like leads, dist caps, rotor arm, there comes a point when you need to admit defeat. I know it strikes at the heart of your masculinity (it does mine) but take it on the chin, some people know more than you do. Generally those who spend 40+hours a week under a car bonnet and have done for 20 years. Link to comment Share on other sites More sharing options...
TomB Posted May 13, 2011 Share Posted May 13, 2011 Is this the week where 1.4k, (or 1.8k using 1.4k bits) have problems? Mine wont idle this morning. I got it to work today with the occasional stall at lights, but it wasnt happy. Oddly it was fine last night. Ive been having bit of trouble with the starter click/ possible weak battery, and I think Ive upset the cold start MEMS by putting a bit of throttle on when cranking to start. When I got to work today I reset the throttle and disconnected the battery from the ECU. After that it idled OK, but stalled after I touched the throttle and returned to idle. I hope a sit and cool down will reset things. Ill pop out at lunchtime and disconnect the ECU for a minute to let it fully reset as I dont think I left it long enough earlier. Any thoughts? Edited by - TomB on 13 May 2011 11:50:22 Link to comment Share on other sites More sharing options...
TeKK Posted May 14, 2011 Author Share Posted May 14, 2011 Minor Update Fitted a new set of HT leads as Number 1 fell apart in my hands upon removal. Upon fitting the new leads, I heeded Angus' information and get the HT lead well away from the crank sensor. Fitted a new ignition coil as I was suspecting the coil itself was old and overheating. However, the misfire still remains. Same issue, run her for a bit and she starts to miss and then gets progressively worse. But I think I'm getting much closer to the source. Earlier in the thread, Mort mentioned stuff stuck in the fuel tank. There's about 1/4 of a tank remaining and the car has been all well if I drive through town at a sedate pace. Opening her up in a 60 zone, the miss got very bad, so I pulled over and the engine actually stalled. I gave it a minute while I checked under the bonnet and restarted her. She took a bit of cranking but then started and was fine, the short drive home she started to miss again. My belief is that it could indeed be the jelly substance mentioned frequently on here or some other contaminate in the fuel, which once I start moving briskly, gets sucked over to the pump/filter, effectively blocking it. So my next step will be to drain the fuel tank, flush it out, refill and see how it goes. Edited by - TeKK on 14 May 2011 16:03:07 Link to comment Share on other sites More sharing options...
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