thehelix112 Posted November 8, 2009 Share Posted November 8, 2009 So my car has been off the road for almost a year, so long that the engine is now very unhappy about life. It'll sputter along running on buggerall cylinders for as long as you can be bothered holding your foot down around 20% throttle. If you stab the throttle it dies, if you take your foot off it dies. And there is a decent amount of blue smoke coming off the engine bay. I'm not sure if its the oil/grease from me touching stuff burning off, or if there is somehow a hideous problem and its ingesting massive amounts of oil? It started like it'd never been stopped, but then quickly developed this problem a few seconds later. I know very little (nothing) about the stock L28E setup, and couldn't both sit in the car to keep it going and look in the engine bay to try and find the source of the smoke. Only other thing I can think of is that it had this problem when it sat for a few weeks previously but then came good by itself. Any suggestions/ideas? Dave Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted November 17, 2009 Author Share Posted November 17, 2009 Little more info. Let it cool down again (during the week) and tried again yesterday. It starts immediately when its cold, running absolutely rich as hell. I'm surprised it runs, the plugs are not looking happy at all, and it blows amazing amounts of black smoke. So its running pig-rich. Is there a sensor that I've misplaced or knocked or has died in the past year that could exhibit this behaviour? As the engine warms up it gets worse until it just won't even fire. Any help appreciated. Dave Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 17, 2009 Administrators Share Posted November 17, 2009 Dave, Check the water temp sensor and it's connections (lower thermostat housing). Other things can cause similar symptoms, but poor WT sensor connections are very common with the age of these cars, and cause behavior very much like you describe. Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted November 17, 2009 Author Share Posted November 17, 2009 Ron, Will do mate. I'll check its connections are correct, and will pull it out and see if it runs differently with it disconnected entirely. Thanks dude. Dave Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 17, 2009 Administrators Share Posted November 17, 2009 and will pull it out and see if it runs differently with it disconnected entirely. Exactly. If it behaves the same with it unplugged, you're likely on the right track Quote Link to comment Share on other sites More sharing options...
spacecase70 Posted November 18, 2009 Share Posted November 18, 2009 also try taking out your injectors and clean them, may have a obstruction in the nozzle that will not let the injectors close from the time it sat. don't forget to clean all the connections on the FI system Quote Link to comment Share on other sites More sharing options...
Ben Posted November 22, 2009 Share Posted November 22, 2009 Check for vacuum leaks, damaged connectors and find out where the hell the smoke is coming from! (e.g. you may have a fractured PCV hose that is leaking onto the exhaust manifold and really screwing up your air metering.) Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 14, 2009 Author Share Posted December 14, 2009 spacecase70, Ben, Thanks so much for the input, much appreciated. The injectors were just cleaned, and I remembered that the exhaust headers developed a huge split recently, and I broke a stud trying to get it off to have it welded up, so it was just welded up on the car, but not completely as he couldn't reach. So thats where the engine bay smoke is coming from. The issue turned out to be a dodgey connection to the drivers-side coolant temperature sensor. There are two sensors on my car, right next to each other (?!). No idea which is what, but the one that you can hardly see (at night with only a desk lamp for light) was the culprit. Next issue, clutch master cylinder is blown out I think. Many thanks guys, Dave Quote Link to comment Share on other sites More sharing options...
Ben Posted December 15, 2009 Share Posted December 15, 2009 NP, your sensors are as follows: Coolant Temp (ECU - 2 pin) Thermotime switch (large, 2-pin, cold start injector control, if fitted) and Coolant temp (gauge - 1 pin) Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 15, 2009 Author Share Posted December 15, 2009 Hmm, so the thermotime switch controls the cold-start injector? Interesting. I thought I tested it when it was struggling by disconnecting the cold-start injector but it didn't make any difference. Maybe I'm mistaken. I assume you're saying that the thermotime switch controls when the cold-start injector runs? And assumedly that if no signal comes from it, it assumes the engine is in cold-start mode and starts dumping fuel in? Dave Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted December 15, 2009 Administrators Share Posted December 15, 2009 Hmm, so the thermotime switch controls the cold-start injector? Yes. Interesting. I thought I tested it when it was struggling by disconnecting the cold-start injector but it didn't make any difference. Maybe I'm mistaken. It shouldn't have made any difference, unless engine temp was below 57F ('78 model. Can't remember if the temp. threshold varied year to year). I assume you're saying that the thermotime switch controls when the cold-start injector runs? Yup. And assumedly that if no signal comes from it, it assumes the engine is in cold-start mode and starts dumping fuel in? No. Other way 'round. Quote Link to comment Share on other sites More sharing options...
Ben Posted December 15, 2009 Share Posted December 15, 2009 Cheers Ron - you beat me to it! Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 15, 2009 Author Share Posted December 15, 2009 And assumedly that if no signal comes from it, it assumes the engine is in cold-start mode and starts dumping fuel in? No. Other way 'round. Hmmm.. so if the signal is 12V it assumes its in cold-start mode? Indicating that I possibly have a short in that circuit? Thanks again for all the great info. Dave Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 15, 2009 Author Share Posted December 15, 2009 I think I say `assume' too much. Quote Link to comment Share on other sites More sharing options...
PhilbertZ Posted December 15, 2009 Share Posted December 15, 2009 When I was troubleshooting my L28E due to failed smog, I blocked off the fuel hose to the cold start valve (in case the Thermotime switch ever fails). The TT switch passed my FSM diagnostic tests, but in CA, I have no need for it, and don't want to risk dumping unneeded extra fuel into the engine. To block it, I disconnected it from the intake manifold, disconnected the sensor and rubber tube from the fuel rail, and inserted a bolt (sans head - hacksawed that off), so it plugged the gas line. Then button it up and you're set - looks "stock" to emissions inspectors Thanks BRAAP for that idea! Good luck - recommend you do the FSM diagnostics - just need a multimeter and a few hours or time - you can eliminate things this way. Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 15, 2009 Author Share Posted December 15, 2009 Phil, Absolutely, that was next on my list of things to do. Great idea with the bolt in line. Dave Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 18, 2009 Author Share Posted December 18, 2009 Rolling again. Thanks guys! Dave Quote Link to comment Share on other sites More sharing options...
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