Dick Whittington Posted May 13, 2014 Share Posted May 13, 2014 I've been trying to help Ross Maclagan (sponsor him here) to fix his starting issue which developed over the winter after the service. The Symptoms ~~~~~~~~~~~~ 1. With no accelerator input, engines starts and then immediately dies for both hot and cold running. Further attempts are worse - seems like it's flooding 2. Engines starts and returns to idle with 3-4 seconds of accelerator input 3. Engines starts, almost dies and then revs build to idle correctly with ~2 seconds of accelerator input 4. Engine has previous idled at ~2000rpm from ferry to home this year coming back from WightBlat 5. When running cold, revs gradually decrease as the engine gets hotter (as expected) The Car ~~~~~~~ - 1.8 K-Series Supersport running on MEMS ECU. - Banner battery - Previously fitted with a relay to overcome the K-click starter issue - Full service over winter by Carbon & Balls Limited (local outfit) replacing the timing belt. - New Brise starter fitted (old starter had damaged terminals, possibly the real reason for the K-click). - K-click relay left in place. Suspected ~~~~~~~~~ a. Air Filter too tight on plastic plenum b. TPS faulty/uncalibrated (does not hunt) c. IACV sticking d. ECU Water Temperature Sender faulty (but revs do drop with temp increase) e. Timing Belt one tooth out (but runs OK after starting) f. Brise Starter faulty Done so far ~~~~~~~~~~~ # TPS/MEMs reset (on, 5 full throttle cycles in 30 seconds, 15 seconds wait, off) # Air Filter a little tight. Loosed and rotated 90 degrees. Butterfly is/was fully closed. # IACV cleaned and observed operation out of casing. Appears to be moving freely in both directions # Lots of BlatChat searching. There seems to be others who have had the same issue (poor starting after fitting a Brise starter) with no definitive explanation why but related to voltage drops. What I think is happening? ~~~~~~~~~~~~~~~~~~~~~~~~~~ While testing the IACV I noticed when the car is turned off, the IACV fully extends to find the fully closed position and then retracts half way (I'll call this "first position") ready to be restarted. When the ignition is turned on the IACV retracts by the tiniest amount (almost unnoticeable) as it initialises, again ready to start. I think this is the correct behaviour for the IACV. What I think is happening is that the Brise is creating a large voltage drop across the Banner battery. The Brise is a more powerful starter than the original and requires more ampage to turn over, more ampage than the Banner is able to supply. When I try to start the engine, the voltage across the battery drops (it was late so have not done a measurement) and the ECU or MFRU loses consciousness for a bit. This causes the IACV to think the ignition has been turned off and so tries to return to "first position" which involves fully closing and reopening ready to start. This starves the engine of oxygen and it dies. Using the throttle is compensating for the lack of air as the IACV closes until it reopens when you release the starter. ISTR that when testing the IACV out of the casing, while plugged in, that it extended when the starter was activated (but it was late in the evening, so can't be sure) The ~2000rpm idle issue could have been the MEMS stuck in a funny state after voltage drop or perhaps a sticky IACV. Possible Solution ~~~~~~~~~~~~~~~~~ So the solution is possibly either or both: - Get a gell battery (Powervamp?) which can supply a high current without a voltage drop. The Banner is quite old. - Removing the unnecessary K-click relay which may be over-supplying to the starter solenoid Further Testing ~~~~~~~~~~~~~~~ - Measure voltage drop across battery on starting - Try starting engine with jump cables attached to supplement the Banner - Try starting engine with the gell battery from my 7 - ? What do you think? ~~~~~~~~~~~~~~~~~~ What do you think, does my analysis seem sound? Anything else worth looking at before trying the battery/Brise angle? Edited by - Dick Whittington on 13 May 2014 12:44:30 Link to comment Share on other sites More sharing options...
ECR Posted May 13, 2014 Share Posted May 13, 2014 As you suggest, try starting the car with jump leads from another good source. This should eliminate the voltage drop problems. I think I'd be looking more closely at the IACV .... Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted May 13, 2014 Member Share Posted May 13, 2014 Yes. And measure battery voltage at rest, during cranking and at idle. IMHO it's impossible to sort out electronic problems without being sure that the smoke has reached working pressure. Jonathan Link to comment Share on other sites More sharing options...
johnv Posted May 13, 2014 Share Posted May 13, 2014 Dick I have the same set up as Ross (banner, brise etc) if you're ReHaBing tomorrow night we could measure the voltage drops on startup to see if they are the same? (I do not have any of these problems at the moment! ) Link to comment Share on other sites More sharing options...
simonpa Posted May 13, 2014 Share Posted May 13, 2014 I've a couple of spare IACVs, if you want to try another. It sounds more like TPS to me. Have you tried resetting it? I think it's ignition on and then press throttle fully 5 (or 7) times. When it resets, you can hear the IACV cyling as well. Also, check the voltage on the TPS - there is a process and voltage range somewhere in the archives. Cheers - Simon Link to comment Share on other sites More sharing options...
LazerBrain Posted May 13, 2014 Share Posted May 13, 2014 I had a similar 2k idle in the distant past when I had battery problems and bump started the car. Once the battery had recharged and the engine was restarted, it was fine. Link to comment Share on other sites More sharing options...
revilla Posted May 13, 2014 Share Posted May 13, 2014 I accidentally left a SatNav plugged into the 12v socket on my Caterham. I know from experience in the tintop that it runs the battery down very quickly. When I put a battery conditioner on it, it did show the battery in a low state of charge; however the symptoms on the Caterham were a bit surprising, and very much like yours. It still cranked over strongly, apparently just as eagerly as when fully charged, but needed throttle to to start and run for the first few seconds. You analysis of what the IACV is doing after an ECU dropout due to reduced supply voltage would make sense. Link to comment Share on other sites More sharing options...
Dick Whittington Posted May 13, 2014 Author Share Posted May 13, 2014 Thanks JV, I suspect you don't have the K-click relay which could be a differentiator. I'm probably not going to be at the Wednesday meeting as I'm supporting my daughter while she does her GCSEs. I'll bring a volt meter along on the weekend for a bit of a probe though. ;-) Link to comment Share on other sites More sharing options...
Dick Whittington Posted May 13, 2014 Author Share Posted May 13, 2014 Simon, Thanks very much. I'll discount the voltage drop first and may very well take you up on your offer as IACVs are too expensive to buy on to test. Link to comment Share on other sites More sharing options...
Dick Whittington Posted May 13, 2014 Author Share Posted May 13, 2014 Lazerbrian and revilla thanks for you info. Nice to know this is not isolated. Link to comment Share on other sites More sharing options...
simonpa Posted May 13, 2014 Share Posted May 13, 2014 Haha - no need to buy them, they are sat in a drawer and available for extended loan! Link to comment Share on other sites More sharing options...
djg Posted May 13, 2014 Share Posted May 13, 2014 I have had these exact symptoms. A brise starter and a banner battery. After all the usual reset ecu, plugs etc it turned out to be the modified main starter cable. It had a carp connector in it that I replaced with a decent one. I can now start to the car with no throttle fine. Hot or cold. As u say a large volt drop caused by too much resistance. Doug Link to comment Share on other sites More sharing options...
Dick Whittington Posted May 13, 2014 Author Share Posted May 13, 2014 Doug, That is very interesting. The leads were also extended on Ross's to handle the change in connector location. I will check that out. Link to comment Share on other sites More sharing options...
Dick Whittington Posted March 16, 2015 Author Share Posted March 16, 2015 Just as a follow up, the issue did turn out to be the battery. Once replaced the car started perfectly. It appears that the old Banner could not supply both the starter motor and the ECU with enough juice so the ECU thought that the ignition had been turned off and so reset to first position. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 16, 2015 Member Share Posted March 16, 2015 Thanks for the update, glad it's fixed.It's surprising but we've now got several examples of what sounds like adequate battery oomph (because it's supporting adequate cranking) but turns out not to be.Recommended multimeter: Draper 60792, but any should do this fine.Jonathan Link to comment Share on other sites More sharing options...
Smithy77 Posted March 18, 2015 Share Posted March 18, 2015 I recently had exactly the same issue with a Brise starter on my 1.6 K. I have reverted to the standard Magneton starter with slightly modified relay wiring and problem solved. Add some decent heat shield to the starter and I believe the K-click problem can be avoided.My battery gave healthy voltage readings, but this isn't always fully representative of the battery health. I suspect that if I replaced the battery for new it might have fixed the issue (the previous owner had no starting issues when the Brise and brand new Banner was fitted 3 years ago), but that's the problem with these high power starter upgrades.... you need the battery in absolute TIP TOP condition to work properly (assuming your using the standard Banner). So you might find you have to replace your battery more frequently using a Brise than if you had a standard starter..... Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 18, 2015 Member Share Posted March 18, 2015 revilla's excellent analysis of what was happening with at least one Brise starter.Jonathan Link to comment Share on other sites More sharing options...
Smithy77 Posted March 18, 2015 Share Posted March 18, 2015 Thanks Jonathan. Yes, I was the guinea pig in that experiment Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 18, 2015 Member Share Posted March 18, 2015 :-)I must keep up!Jonathan Link to comment Share on other sites More sharing options...
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