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Discussion Starter · #1 ·
I have a 89 burban 350 tbi 142,000 miles, that i pick up in Oct. I live in Ft Worth, Texas. Last week after it set for 3 days without me starting it. I could not get it running. I tried about 50 times to start it. It has a new battery,starter, plugs,wire,coil,dist. cap,rotor,fuel filter. It was cold (35-40 degrees) here. I took the burban to a shop and let it warm up in the garage and after a couple of hours she started up after about 10 tries. She backfired and flames came out of the carb. Once it runs it runs good. I check the timing and it's in time and it is getting fuel. I can let it set over night and it will run the next day after about 3 trys. Not sure where to start looking.

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I wonder if the distributer has been out and moved into wrong postion? (i.e. couple of teeth off?)Cuz the backfiring makes me think there still is a timing issue....Anybody else?
 

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Timing and possibly a fuel/air issue. The hard cold start time reduced by warming in the garage could be an indicator of either a dirty TBI, possibly fouled or dirty plugs, cold start system not working properly, or even a very dirty air filter. Possibly a combination of everything.
Clean the TBI, run Sea Foam or your favorite intake cleaner through the system.
Then check the plugs for fouling, check the air filter, and check the ignition system for proper spark.
The next time it has a cold start issue before you get it running pull a plug and see if it's flooding out.
See if this doesnt clear-up the slow cold start issue. At 142K unless you positively know the maintenance performed before you bought it assume it had nothing done.
 

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I know this is a TBI engine, so I am not sure where I'd start... I know that I had major issues with the 350 SBC I have in my '68 Firebird, (same problem you describe), but they were all carb. related. Once I replaced it (so yeah to Edelbrock!), my problems went away entirely. (and the morale to that story for me is no more Holley !)
 

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Discussion Starter · #5 ·
Thanks for all the help. She has new plugs/wires/air filter/fuel filter. I started her this morning and it started on first try. No back firings. I talked to a tech today and he told me that the diaphragm in the fuel pump is the problem. He says when it is cold outside the diaphragm in the fuel pump shrinks and fuel is not being push to the carb. Once it warm up it the diaphragm expand which then alouds fuel to pass at the correct fuel pressure. As for the back firing he could not explan that. :neutral: Will replace fuel pump soon and see if that fixes the problem, and let everybody know if that was it.
 

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Discussion Starter · #7 · (Edited)
Replace fuel pump

I replace the fuel pump yesterday, so now I have to wait till it turns cold sometime tonight. :neutral: It was the OEM fuel pump in her. Will let you know hopefully tomorrow if that fix the problem. Thanks for everybody help with this.
 

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Ignition module?

They can be temperamental, work then not. But you should test it before replacing. Can’t remember the test procedure.

They are not that expensive, I had to replace the one on our 94 and it was under 50 bucks at NAPA.
 

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I replace the fuel pump yesterday, so now I have to wait till it turns cold sometime tonight. :neutral: It was the OE fuel pump in her. Will let you know hopefully tomorrow if that fix the problem. Thanks for everybody help with this.
It's been warm the last few days in DFW! Good luck with that tonight.
 

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Discussion Starter · #10 ·
Did it start????

Got cold here last night and went to the burban at 7am and it:gasp: ...................started on the first try.:happy:Thanks for all your help. I did check the ignition module and it is new.
 
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