Help!! rough idle, blacks smoke, maf?
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Joined: Oct 2002
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Help!! rough idle, blacks smoke, maf?
Hi all
Im having some problems with my car i hope yall can help me with. Here is the scoop. Last fall i bought a 89 T/A off of ebay.The guy i bought it from replaced the 305 tpi with a 350 gm goodwrench 350 tpi. It ran good with no problems. I stored it a few months and then i took it out in mid april. Since the i ve had a few things done to it. I had flowtek headers put on it. I know everybody hates these but there better then the stock 305 manifolds.I had a full tune up on the car replaced the o2 senser and wires and distrubiter, and plugs. The car ran preety good foer awhile. The only diffrence i noticed was it would take a minute it to warm up otherwise it would die on you, But it ran good. My service engine light would come off and on sometimes.After i had the headers put on i had my mechanic adjust my timing.It was set at 0. He looked up in his manuel and it said out 350 cars should be set + 10 degress and in addation for the high alttitude here in Denver Colo to at about 4 more degrees.So its set at 14 degrees now. Well after driving my car for a few months i thought i better check why my engine light was on. Thats when my problems started
I took it to autozone and he checked it with paperclip method. after checking the flashes he said showed a code 36. He said i probabaly needed a new maf. so i bought 1. We disconnected the battery fo a minute and the service engine went off. I was like cool problem solved!!I drove it for few days and then the light came back on
Iwas like **** i guess that wasnt my problem so i got my old maf back.Well a couple days after that i was driving to work and noticed my car was running crappy with a very rough idle.I was like **** it must be my maf. So i went to checkers this time and got another one put on my car.
It didnt help at all this time actually it got worse the car wouldnt idle at all and it was spitting out black smoke from my exhaust.I didnt know what to do so i took it to mechanic and they charged me 85 dollars and said that my new maf was bad. They said autozone and checkers sold junk and that i should but a ac delco maf from them for 550.00 dollars.i was like no way ill just exhange my maf for another one from checkers.I did ths and still the same problem! I did a search here hoping to find something about this problem.I came up with that maybe mi IAC was bad or dirty. I took my IAC out an cleaned it with carb cleaner it was very dirty, it looked like black soot was on it. I put it back in and it ran worse it wouldnt idle and black smoke was coming out of my exhaust.i thought ok ill buy a new IAC and see what happens. I bought a new one and noticed that the spring pointer thingy on my old one was sticking out alot more than on my new one.Put the new one in and now it idles,but very rough at first. went to drive it and the idle smoothed out. Once i start driving it runs good now.My problem now is when i shut the car down and go to start it the next day it idle real rough and kicks out black smoke still. When i take off it starts to run good and the idle gets smooth.yesterday i got home and shut it off,then Cranked it back up after a few seconds It idles rough for a few seconds and blew out black smoke and the the idle smoothed out and the black smoke went away.
If anybody can help out here i would be very grateful.sorry baout it being so long. Thx
Im having some problems with my car i hope yall can help me with. Here is the scoop. Last fall i bought a 89 T/A off of ebay.The guy i bought it from replaced the 305 tpi with a 350 gm goodwrench 350 tpi. It ran good with no problems. I stored it a few months and then i took it out in mid april. Since the i ve had a few things done to it. I had flowtek headers put on it. I know everybody hates these but there better then the stock 305 manifolds.I had a full tune up on the car replaced the o2 senser and wires and distrubiter, and plugs. The car ran preety good foer awhile. The only diffrence i noticed was it would take a minute it to warm up otherwise it would die on you, But it ran good. My service engine light would come off and on sometimes.After i had the headers put on i had my mechanic adjust my timing.It was set at 0. He looked up in his manuel and it said out 350 cars should be set + 10 degress and in addation for the high alttitude here in Denver Colo to at about 4 more degrees.So its set at 14 degrees now. Well after driving my car for a few months i thought i better check why my engine light was on. Thats when my problems started
I took it to autozone and he checked it with paperclip method. after checking the flashes he said showed a code 36. He said i probabaly needed a new maf. so i bought 1. We disconnected the battery fo a minute and the service engine went off. I was like cool problem solved!!I drove it for few days and then the light came back on Iwas like **** i guess that wasnt my problem so i got my old maf back.Well a couple days after that i was driving to work and noticed my car was running crappy with a very rough idle.I was like **** it must be my maf. So i went to checkers this time and got another one put on my car. It didnt help at all this time actually it got worse the car wouldnt idle at all and it was spitting out black smoke from my exhaust.I didnt know what to do so i took it to mechanic and they charged me 85 dollars and said that my new maf was bad. They said autozone and checkers sold junk and that i should but a ac delco maf from them for 550.00 dollars.i was like no way ill just exhange my maf for another one from checkers.I did ths and still the same problem! I did a search here hoping to find something about this problem.I came up with that maybe mi IAC was bad or dirty. I took my IAC out an cleaned it with carb cleaner it was very dirty, it looked like black soot was on it. I put it back in and it ran worse it wouldnt idle and black smoke was coming out of my exhaust.i thought ok ill buy a new IAC and see what happens. I bought a new one and noticed that the spring pointer thingy on my old one was sticking out alot more than on my new one.Put the new one in and now it idles,but very rough at first. went to drive it and the idle smoothed out. Once i start driving it runs good now.My problem now is when i shut the car down and go to start it the next day it idle real rough and kicks out black smoke still. When i take off it starts to run good and the idle gets smooth.yesterday i got home and shut it off,then Cranked it back up after a few seconds It idles rough for a few seconds and blew out black smoke and the the idle smoothed out and the black smoke went away. If anybody can help out here i would be very grateful.sorry baout it being so long. Thx 
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When you added 45 cubes to the engine, did you change the PROM in the ECM, or the injectors? The stock PROM for a 305 is going to meter fuel appropriate to a 305's requirements until you reach closed-loop mode (warmed up).
What is the fuel pressure?
What MAF are you using now?
What is the fuel pressure?
What MAF are you using now?
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Joined: Oct 2002
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Hi vader. yeah they put in a 350 chip in the car, and it has the new maf that i got from checkers auto parts.. It currently has the 305 injectors though.Do you yhink i should go to the 350 injectors?
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From: Trumbull County Ohio
i've heard about a LOT of people having problems with aftermarket sensors: mafs, o2s, cts. I've even had it happen to me once.
Honestly, i'd only get an a/c delco sensor. They are expensive, but you could go around to junkyards and look for one if you're short. Or there's a couple websights around that sell a/c delco parts at a marginal discount.
Honestly, i'd only get an a/c delco sensor. They are expensive, but you could go around to junkyards and look for one if you're short. Or there's a couple websights around that sell a/c delco parts at a marginal discount.
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From: Trumbull County Ohio
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Instead of dropping a few hundred samolians on a different MAF, check the one you have. A digital voltmeter connected to the 'B' and 'C' terminals on the MAF should provide a voltage reading when teh engine is running. For a 350 with a stock cam at a normal idle RPM, the MAF should output about 800-900mV.
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