Sounds like you've got a bad fuel leak. Pull the air cleaner off and blip the throttle. Do you see a backfire through either throttle body?
84 Crossfire Problems
Thread Starter
Intermediate
Joined: May 2005
Posts: 46
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From: Wheaton Ill
84 Crossfire Problems
Well I have had the injectors rebuilt and cleaned and the diaphragms on the injectors replaced. I have had the distributor checked. What I have is at part throttle and not all the time, I get a backfire thru the TBI with flames running in the driveway. I suspect the miss in the road is the backfire. I have done the laptop hookup and do not see anything that stands out. Suggestions as to were to start. I have new distributor cap and rotor also.
Le Mans Master
Joined: Sep 2009
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From: Vermilion OH
definatly check for fuel leaks first and foremost! might want to check timing and check for faulty ignition wires that may arc and ignite the fire. are you sure all of the fuel line connections are tight on the throttle bodies? did you use any pipe dope on the the threaded connections to ensure that there would be no leaks?
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
For the miss in the road, see if you can get the City of Wheaton to come and fill the pot hole. What are the "diaphragms on the injectors" and did replacing them help? How about the checking of the distributor. Was anything revealed or fixed? What is the "laptop hookup"? Do you have a scanner? Diagnostic software? What do you mean "do not see anything that stands out"? What would or could? Have you checked for set trouble codes? It seems that a burning driveway is a serious matter.
RACE ON!!!
RACE ON!!!
Thread Starter
Intermediate
Joined: May 2005
Posts: 46
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From: Wheaton Ill
Okay to clear things up. I am running the car in the driveway with the cleaner off to see in the tbi's. The car idles fine. After it warms up if you hit the throttle, sometimes the engine revs up, sometimes it pops thru the tbi's and sometimes the pops have the added flame. It does not happen constantly, it is total intermittent. I have used the laptop with the WINDL program to record data.
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Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
22, TPS is a no brainer. Do you now have the voltage properly set? Is it smooth through out it's travel? 24, MAP, ditto. Is it hooked up and responding properly. No vacuum leaks? The 42 is possibly from not reconnecting the EST wire after setting the base timing.
Backfiring back through the intake could be lean on acceleration. Is the fuel pressure keeping up, under load? A vacuum leak could also cause it to lean out and might trigger a 24. If the EST is still disconnected that will cause problems. How about the secondary wiring? Any crossed wires? Sometimes it help to have some one not too familiar check you. If you you stare at a problem long enough, it starts to look right. After all the work on the TBs were they synchronized, balanced, and the minimum air adjustment made? Unless you have a burnt valve it should be just a matter of getting things checked out and properly adjusted. Keep a fire extinguish handy. Driveways are expensive.
RACE ON!!!
Backfiring back through the intake could be lean on acceleration. Is the fuel pressure keeping up, under load? A vacuum leak could also cause it to lean out and might trigger a 24. If the EST is still disconnected that will cause problems. How about the secondary wiring? Any crossed wires? Sometimes it help to have some one not too familiar check you. If you you stare at a problem long enough, it starts to look right. After all the work on the TBs were they synchronized, balanced, and the minimum air adjustment made? Unless you have a burnt valve it should be just a matter of getting things checked out and properly adjusted. Keep a fire extinguish handy. Driveways are expensive.
RACE ON!!!
Race Director
Joined: Apr 2003
Posts: 17,698
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From: moraga ca
Okay to clear things up. I am running the car in the driveway with the cleaner off to see in the tbi's. The car idles fine. After it warms up if you hit the throttle, sometimes the engine revs up, sometimes it pops thru the tbi's and sometimes the pops have the added flame. It does not happen constantly, it is total intermittent. I have used the laptop with the WINDL program to record data.
Thread Starter
Intermediate
Joined: May 2005
Posts: 46
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From: Wheaton Ill
The problem seems better after this, I drained what gas was in the tank and put fresh in. Seems to run better in the driveway, but was to late last night to road test. The history on the motor is it is high mileage, but what I had was a trans problem with 3-4 (burned out). The car sat for a 1 1/2 year due to divorce. When I went to rebuild the trans, it did run fine putting it into the garage. But after pulling engine and trans, rebuilding the trans and two months time in the garage it would not run. Problems found was rust in the diaphragms and the injectors in the TBI's. Had reconditioned injectors and a new rebuild kit for the TBI done. Normally with computer engines I set the timing by putting in diag mode, but one post here indicated I need to do it different?
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
To set your timing properly, first warm up the engine. With the key "Off" disconnect the EST wire near the brake booster. Do not have any terminals on the ALDL shorted. Start the engine, and at the lowest possible idle speed, set the timing to 6° BTDC. That is the spec for the base timing. Shut off the engine, reconnect the EST wire and disconnect the battery for a short while to clear the code 42 that was set while the engine running with the EST disconnected. Done!
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