Calgary280ZT Posted September 30, 2009 Share Posted September 30, 2009 Hey guys Well, we fired up the Z tonight after fixing the stuck #6 intake valve on my Rebello head. Now I have a problem I don't understand. The car will start dead cold (in Calgary it's now around 10C), but not when it's warm. Too much fuel. We took the plugs out and cleaned them, sprayed compressed air into the cylinders, then it started right up. In the warmer summer months (20-30C) it started all the time...didn't idle well until reaching operating temp, but it started ok. I checked the starting fuel rate engine temp chart. from -60 to +22 the rate is set at 10 ms. On my fuel map, at 750 rpm the ms range from 1.1 to 3 under 0 - 29% load. So my reading (I'm a noob at this) is that the car is getting anywhere from 3-5 times as much as gas it would when idling when warm. The part I don't understand is why it started fine in during the warm summer days and floods itself now? I haven't changed the map at all (car hasn't run since late June/early July). There is no air intake temperature sensor on it. So I don't see how the V500 could know that the air temp is lower now. But it acts just like it knows that above 22C give it no extra gas and below 22C give it a lot more. Hope I've explained the problem so you can understand it. Tomorrow Z240 and I are going to play with the starting fuel rate and see if we can get this licked. Just looking for insights if you got em.... Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted November 2, 2009 Share Posted November 2, 2009 That seems like a lot of fuel for the CLT enrichment. Are you sure you were getting into that 10ms range before? Try adding more like 50~75% more fuel. I have noticed a lot of basemaps from cars based out of very warm climates typically have nowhere near the right amount of fuel for cold start (too rich). Quote Link to comment Share on other sites More sharing options...
hughdogz Posted November 2, 2009 Share Posted November 2, 2009 Hi Calgary, I got my configurations from Ron and KTM. The cylinder head (or coolant) temp sensor will know it's colder now. The engine temp enrichment is 0% at 80*C but 20% at 10*C. The air temp modifier is only +/- 5% max. At most it should only be 25% enrichment @ 10*C. I have 460cc/min injectors and the starting squirt time is 7ms. Here are my starting rate fuel trims (in case yours are different) Hope this helps... Quote Link to comment Share on other sites More sharing options...
ktm Posted November 2, 2009 Share Posted November 2, 2009 Mark, the coolant temp and intake air temp modifiers are expressed as percentages not ms. Send your map to Hugh and I to take a look at. Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted November 3, 2009 Share Posted November 3, 2009 Mark, the coolant temp and intake air temp modifiers are expressed as percentages not ms. Send your map to Hugh and I to take a look at. Yeah, I figured, I just noticed he said 10ms (as if he was watching the actual calculated pulsewidth when cranking or something). That sounds high; particularly for bigger injectors. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted March 31, 2010 Author Share Posted March 31, 2010 Hey guys, been a while, but I'm back. I currently have starting fuel rate set at 25 ms from -60 to +20C, then dropping to 20 ms to 100C. The post start is set at 100% from -60 to 0C, the dropping to 50% from 0 to 20, and stepping down to 25% at 80, after which it is 0. These settings are probably insanely rich, but the darn thing starts reliably now. FYI, JimCanuck figured out my starting problems were a worn ignition switch. I've figured out how to hold my tongue right so it starts all the time now (but do have to crack the throttle valve to let some air in or it floods in a heartbeat). My plan, now that the car is running reliably again, is to start cutting back on the start and post-start enrichment until I get it right. Thanks for all the help!! Yeah, I figured, I just noticed he said 10ms (as if he was watching the actual calculated pulsewidth when cranking or something). That sounds high; particularly for bigger injectors. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted August 22, 2010 Author Share Posted August 22, 2010 Quick update...now starting fuel rate set at 6 ms...it starts, but not well, plan to bump it up to 8 or 10. But a far cry from 25. How it even started at 25 I'll never know. Post-start enrichment is set at Wolf's recommended 40% sloping to 30% at operating temp. and that seems to work well. I've also tuned the lower part of the fuel map so I'm not running horribly rich like I was before. Gas mileage has jumped to high teens from 8-10 mpg...lol Plan to tackle the cells above 36% load with great care...my O2 sensor isn't working and I can't get it on a dyno before making the trip back to the West Coast Friday. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 23, 2010 Share Posted August 23, 2010 Leave the starting fuel rate alone and adjust the Starting Fuel Rate Engine Temp curve under Fuel - Fuel Modifiers - Starting - Starting Fuel Rate Engine Temp. Right now with all of the modifiers (engine temp, air temp, starting fuel rate, etc.) my initial fuel rate is around 9 ms when starting cold. You can see this in the upper right hand corner of the display under Inj 1. I am still adjusting it as it still takes a few cranks to turn over when cold. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted August 24, 2010 Author Share Posted August 24, 2010 Bo, set at 10 ms this morning, fired right up. I'll check out the curve you're talking about. I'm feeling pretty comfortable with the lower/off boost part of the map. Decent driveability and gas mileage around 20 mpg. But under boost worries me. Incredibly rich...needs to be leaned out, but I think my O2 sensor is buggered. Gotta figure out a solution to that first.... M Leave the starting fuel rate alone and adjust the Starting Fuel Rate Engine Temp curve under Fuel - Fuel Modifiers - Starting - Starting Fuel Rate Engine Temp. Right now with all of the modifiers (engine temp, air temp, starting fuel rate, etc.) my initial fuel rate is around 9 ms when starting cold. You can see this in the upper right hand corner of the display under Inj 1. I am still adjusting it as it still takes a few cranks to turn over when cold. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 24, 2010 Share Posted August 24, 2010 Mark, Glad to hear it. However, your true starting fuel rate is most likely more than 10 ms. Wolf uses the engine temp and intake air temp to modify the fuel rates, both starting and running. Next time you have Wolf hooked up to the car and before you start it, look in the upper right hand corner under Inj 1. It will tell you the true starting fuel rate. Do not adjust your starting fuel rate to match that value though. My starting fuel rate is 6 ms that is adjusted upwards using the curve I mentioned before and the engine/IAT scaling factors to 9 ms. As for the wideband, do a free air calibration. The LC-1 manual tells you how. You should remove the O2 sensor from the exhaust downpipe to expose it to "free air". There is a ground wire that you ground and the wideband will go through a calibration process that takes 1 to 2 seconds. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted August 27, 2010 Author Share Posted August 27, 2010 Thanks again Bo. I'll work on it when I get back to Calgary after the Sept. long weekend....Friday's the Z is off to its new home in White Rock, BC!! BTW, funny problem you may be interested in...as part of tuning, I advanced the timing 1.5 degrees from 0 - 36% load and 0 - 4,000 rpm. Achieved much better off boost driveability, no pinging, I'm very happy with the changes....except for one thing. Boost response is now terrible. I really have to put my foot into it to get up to 8 or 9 lbs and very little at lower rpms. and when it is at full boost it has lost power, not gained it. Whaddya think? Boost issues caused by timing changes or something else? Quote Link to comment Share on other sites More sharing options...
rejracer Posted November 8, 2010 Share Posted November 8, 2010 Mark, Increasing timing at lower revs/loads will decrease boost response. What is happening is the exhaust gasses are burning more completely in the chamber. This is a good thing from an economy standpoint. Since the gasses are burning in the chamber (and not in the exhaust manifold), they are losing temp as they exit the chamber. It's this loss in exhaust temp that you are feeling. Have you monitored egt's before and after the timing change? Quote Link to comment Share on other sites More sharing options...
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