i got an 85 supra and was wondering why i had a lack of power. come to find out cylinders #1 and #4 are not firing. I installed new plugs, wires, distributor cap and rotor and still have a lack of power. What else could it be?
Are the cylinders firing now, after your tune up or no? If they aren't, have you checked to make sure they are getting spark? Thats the first place to start. If they are getting spark, then it would seem to me to be a fuel delivery problem... and since its localized to those two cylinders, I would say it may be an injector issue.
When you pulled the old plugs, what did they look like? Did they show normal wear and buildup or they show signs of lean/rich/etc...
after the tune-up the cylinders are still not firing. when i pulled the old plugs they were black but not to the point of having buildup. but it did seem like it was running rich. the plugs on cylinders #1 and #4 did show signs that they were getting a small amount of spark but nothing like the other cylinders plugs.
when you say fuel delivery do you mean the fuel pump, fuel filter or just the injectors?
I would actualyy check the spark with a timing light,or pull the 2 plugs and do the blue spark check.But',I'm with Bob,injector problem,is what it sounds like.Ignitor problem would be no spark at all,or very weak in all cylinders.
if it is the ignitor then could that be the reason why i have hardly any power. i have an extreme lack of power. now that i think about it that could explain why it seems like my car has absolutely no power at all. so i'll try upgrade my ignition components and see if it helps. by the way thanks for the help it's greatly appreciated.
Having had two ignitors go on me,one while driving and one when I tried to start in a parking lot, I never experienced a loss of power....okay, well, not "less" power, just NO power. I'm not saying that it isn't your ignitor, just ALWAYS open to other possibilities...
Sounds like a fuel delivery problem to me. A bad igniter generally either causes misfiring or just plain quits altogether and leaves you stranded in the most inappropriate place. How about ECU codes?? Are their any codes stored in the ECU? If not, check the injector connectors on cylinders 1 and 4 and see if the wire terminals in the connectors are making contact with the injector terminals. Sometimes the wire terminals in the connectors like to slide up into the rubber boot, keeping the injectors from firing. Black plugs usually indicates carbon from either a rich mixture or oil fouling. If the injectors on 1 and 4 aren't firing, those two cylinders will pump air into the exhaust manifold and the 02 sensor will detect the excess 02 and tell the ECU to richen up the mixture which in turn causes the other four cylinders to run rich. Check the connectors!