travishoover Posted February 4, 2006 Share Posted February 4, 2006 Hello Board !! I own a 91 Legacy L Auto Trans 16valve Fuel injected.. She has 187,000 miles I just changed the Plugs and Wires, The # 2 Plug has Black Sooty chalk like around the plug,, Idels around 800,,under a grand,, has a severe Miss on acceleration and back fires,,she loses power,,But no smoke out the pipes.. Injectors sound ok and all the same,, The Back fire is only occurs at starting while ideling low,then on accel.. Please get back to me ASAP so my Subby dont die !!!! Thanks Quote Link to comment Share on other sites More sharing options...
Suzam Posted February 4, 2006 Share Posted February 4, 2006 Did the problems exist before you did the work, or after? Quote Link to comment Share on other sites More sharing options...
travishoover Posted February 4, 2006 Author Share Posted February 4, 2006 Did the problems exist before you did the work, or after? Thanks For The reply ! but yes the problems were there before any work was done...thats why we did the work ?? Quote Link to comment Share on other sites More sharing options...
cowboystrait Posted February 4, 2006 Share Posted February 4, 2006 replace ur distrubter wires an all try that see how thats works;) Quote Link to comment Share on other sites More sharing options...
travishoover Posted February 6, 2006 Author Share Posted February 6, 2006 Unfortunately I don't think there are any distributor wires as this model has electronic fuel injection. I still am looking for some suggestions, I really want to do the work on this car myself, but I am at a loss to know where to go next, Please Help! thanks! replace ur distrubter wires an all try that see how thats works;) Quote Link to comment Share on other sites More sharing options...
beezer Posted February 7, 2006 Share Posted February 7, 2006 I might get a fuel pressure gauge and a repair manual and test the system. I would also check the resistance values acrosss the injectors, I don't remember what the values should be. If the there is a check engine light on, then I would go to Legacy777's website www.surrealimage.com to get the instructions on how to retrieve them. To me it seems like raw fuel is getting dumped into the exhaust causing the backfire. There can be other reasons too. I would check out the coil pack and the igniter. Is your charging system in good condition, ie. the battery, alternator. 12V with the car off, 14-15 with the car running. Getting a repair manual is a good idea, it helps with some of the testing. If the CEL is on I would start there, if it isn't then I would check the coil pack ignitor and the charging system and the fuel system. If this doesn't go anywhere I guess you could swap injectors to see if the sooty black stuff follows the injector or is related to that particular cylinder. Good Luck Beezer Quote Link to comment Share on other sites More sharing options...
tcspeer Posted February 7, 2006 Share Posted February 7, 2006 I agree on the coil pack. And it is easy to check and change. I might get a fuel pressure gauge and a repair manual and test the system. I would also check the resistance values acrosss the injectors, I don't remember what the values should be. If the there is a check engine light on, then I would go to Legacy777's website www.surrealimage.com to get the instructions on how to retrieve them. To me it seems like raw fuel is getting dumped into the exhaust causing the backfire. There can be other reasons too. I would check out the coil pack and the igniter. Is your charging system in good condition, ie. the battery, alternator. 12V with the car off, 14-15 with the car running. Getting a repair manual is a good idea, it helps with some of the testing. If the CEL is on I would start there, if it isn't then I would check the coil pack ignitor and the charging system and the fuel system. If this doesn't go anywhere I guess you could swap injectors to see if the sooty black stuff follows the injector or is related to that particular cylinder. Good Luck Beezer Quote Link to comment Share on other sites More sharing options...
travishoover Posted February 7, 2006 Author Share Posted February 7, 2006 Thanks so much for your help! I'll give those suggestions a try. I agree on the coil pack. And it is easy to check and change. Quote Link to comment Share on other sites More sharing options...
86 BRAT Posted February 14, 2006 Share Posted February 14, 2006 Hello Board !!I own a 91 Legacy L Auto Trans 16valve Fuel injected.. She has 187,000 miles I just changed the Plugs and Wires, The # 2 Plug has Black Sooty chalk like around the plug,, Idels around 800,,under a grand,, has a severe Miss on acceleration and back fires,,she loses power,,But no smoke out the pipes.. Injectors sound ok and all the same,, The Back fire is only occurs at starting while ideling low,then on accel.. Please get back to me ASAP so my Subby dont die !!!! Thanks also sounds like #2 plug wire is not making good cotact on the plug or is shorted Don Quote Link to comment Share on other sites More sharing options...
OB99W Posted February 14, 2006 Share Posted February 14, 2006 [...]The # 2 Plug has Black Sooty chalk like around the plug,,Idels around 800,,under a grand,, has a severe Miss on acceleration and back fires,,she loses power,,But no smoke out the pipes.. Injectors sound ok and all the same,, The Back fire is only occurs at starting while ideling low,then on accel.. Dry soot typically indicates an overly-rich mixture; if it's only happening in one cylinder, probably that injector is staying open more/longer than it should. Backfiring is when there's ignition of the mixture at the intake. You probably mean "afterburn", which occurs in the exhaust system due to unburned fuel being ignited by the heat there. With only one cylinder misbehaving, afterburning occuring and a catalytic convertor, you probably won't see much unusual at the tail pipe. In my opinion, the problem is somewhat less likely to be ignition-related, since a misfire due only to bad spark tends to not result in as much soot, but that unfortunately doesn't completely rule out the coil pack. When an ignition scope isn't available, I've sometimes used a timing light and see if it will trigger the same on the suspected plug wire as it will on the others. If not, ignition becomes a stronger suspect. Quote Link to comment Share on other sites More sharing options...
OB99W Posted February 15, 2006 Share Posted February 15, 2006 I've been giving the problem a bit more thought, and it seems the following might be of interest: http://endwrench.com/images/pdfs/IgnitionCoil.pdf http://endwrench.com/images/pdfs/DirectIgnition.pdf http://endwrench.com/images/pdfs/IgnitionCoilSum04.pdf Assuming a '91 has the type of coil pack described in the links above, it appears unlikely that a bad coil in the pack would cause only one cylinder to be affected. If an internal resistor or connection in the pack is bad, a resistance check should reveal it. It would also seem that could be checked by swapping plug wires for cylinders 1 and 2 at the pack end (if they reach); the problem should move to cylinder 1 if the pack is the cause. If the coil pack passes, then I'm feeling even more strongly that an injector working "overtime" is a likely culprit. Under any circumstance, don't run the engine more than absolutely necessary until the problem is fixed. Otherwise, you may be buying a new catalytic converter soon, too. EDIT: Considering the mileage, there's possibly a valve problem. A compression/cylinder-leakdown test should reveal that. Quote Link to comment Share on other sites More sharing options...
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