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Discussion Starter · #1 ·
Ran the 04' TB twice today. Late in the day we had a very wet/humid storm for several hours. Went to leave and unit would not start. Have been getting intermittant check engine light for a few weeks. Light always went out after a few trips and engine ran great. Any pointers on where to start the diagnosis
process? Should I have it towed in to a shop?

Thanks in Advance! :confused:
 

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There should be stored codes with a clue as to what was wrong. Getting them read might need a shop if yo have a trusted one. You may also have a coincidental failure of the ignition switch, a common problem you can search for. We can't advise about towing to a shop unless we know what kind of wrench you are, and how much you need the vehicle, and how frugal you are.
 

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If the engine is cranking and turning over but its not starting then i would assume its a bad fuel pump. Also need to check spark plugs to see if they are getting power.
 

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If the engine is cranking and turning over but its not starting then i would assume its a bad fuel pump. Also need to check spark plugs to see if they are getting power.
:iagree:, that's the place to start. We need fuel and electrical power to fire the engine.
Turn on the key, don't crank. Listen for a motor running at the rear. You should be able to hear the fuel pump run and then stop when the pressure is up.
Ok on fuel pump? Then you need electric power to fire the plugs.
Not ok on fuel pump? Then you may need a new pump. However, this is also a possible electrical problem (no power to run the pump).
If you think there is an electrical problem, it is probably the ignition switch.
 

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Another thing to check if you hear no fuel pump sound is the fuse. Hate to replace the pump and find out in the end that it was only a blown fuse. ouch
 

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Discussion Starter · #6 ·
Fuel pump and/or other parts

Had TB towed to shop. Mechanic sprayed something in to air intake and it tried to run. He then replaced fuel pump, filter and cleared 7 codes. The engine started fine and then check engine and REP light came on. Engine won't run at any speed other than 1,000 rpm. (diagnostic meter couldn't lower the RPM by command) The air intake sensor shows -60F when it's actually 72F (needs replaced) Also had the REP light on coldest day of Winter in January. (Warmed up engine and cabin, then restarted fine with no lights) I have had on and off check engine light for at least a month or so. Could the air sensor be causing all this stuff or is it likely something else? I am starting to wonder if the fuel pump was bad or if clearing the codes allowed it to start. (Read another post where wouldn't run and then clearing codes allowed it to start) I have spent $650 and I still can't drive the TB. Can anyone give me an idea of what to try next. I don't want to replace everything and be back at square one.

Thank You
 

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I am starting to wonder if the fuel pump was bad or if clearing the codes allowed it to start. (Read another post where wouldn't run and then clearing codes allowed it to start) I have spent $650 and I still can't drive the TB. Can anyone give me an idea of what to try next. I don't want to replace everything and be back at square one.

Thank You
Sorry, clearing codes is not going to fix the problem and let it start. It just gets rid of history (like clearing cookies in your pc).
We need to know the code(s) numbers that are causing the current problem. These should be the only codes currently stored.
 

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Discussion Starter · #8 ·
Information Update

Just an update for all that gave advise. When fuel pump died it back-fed high voltage to the PCM. Replaced the computer and pedal travel sensor. So far, so good. Has anyone ever heard of this happening?

Thanks Again
 

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It can also be the anti-theft system which is electronic shut off to the fuel pump so it will turn over but wont start I have never seen it happen on a TB before but every other GM product it deos. Turn the key to the on position leave it about 10-15 minuits turn it off and try and start it. If you turn your key to fast it arms its self thinking it is being stolen.
 

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Has anyone ever heard of this happening?
Never. Did you get to keep the old PCM so somebody else can try it to confirm it's really bad. Not that we distrust mechanics, but the PCM is designed to be protected from the usual kinds of wiring shorts and peripheral failure modes.
 

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Never. Did you get to keep the old PCM so somebody else can try it to confirm it's really bad. Not that we distrust mechanics, but the PCM is designed to be protected from the usual kinds of wiring shorts and peripheral failure modes.
:iagree:, 90% of the time when a PCM is blamed, there is usually a bad ground that was the real problem.

I would also say you did not have a bad fuel pump. My guess, is that your back-yard mechanic is a parts changer without proper diagnostic equipment.
 
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