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88 tbi running rough...

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Old Sep 3, 2009 | 02:07 PM
  #1  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
88 tbi running rough...

hi i am having a problem with my 88 camaro with a 305 tbi two days ago the car started right up and ran great (with a jump the batterys dead) its got new plugs wires and a cap and rotor. and i went to start the car last night and it took a while for the batt to charge up to start it (jump again) and when it finaly had enough juct to start it started but it isnt running right now its really boggy and it wont idle very long without dieing and if you try to rev it up it kinda sounds like its cutting out my uncle thought it may be because the battery is dead? its not getting enough power to the coil is this a possibility? or is it more likely that the fuel filter is pugged or something like that im in the middle of trying to replace that i was told the fuel pump is new but the old one is still good and i have it should i try that?
any ideas what it could be? thanks guys
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Old Sep 3, 2009 | 03:20 PM
  #2  
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Re: 88 tbi running rough...

you know you have a charging problem, fix that before chasing anything else.
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Old Sep 3, 2009 | 06:33 PM
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

i fixed the battery i belive it was just because it hasnt been started and run for a while because i just bought the car about two weeks ago and isnt regisered yet ive just been working on the interior i belive the batt just died from rolling the windows up and down and using the radio without the car running i put the new fuel filter in it and ran it for a bit but it diddnt help the battery is now charged back up though heres a vid of it running

http://www.youtube.com/watch?v=6UKZSHn6eWU
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Old Sep 3, 2009 | 08:52 PM
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Re: 88 tbi running rough...

The first think I'd check would be all the vacuum lines, especially the one that runs to the MAP sensor up on the cowl. Once you've made sure all the vacuum lines aren't leaking or broken, the other thing that can cause a TBI to run rough is if the o-rings around the two injectors have gone bad. This will cause them to stumble badly and act just like a carb when it's loading up from too much fuel. Take off the air cleaner lid and check the spray pattern of the injectors when you give it a little gas. It should be a fine, cone-shaped spray. If it's just drizzling or dripping out, you probably have bad o-rings. You can get new ones with a basic TBI rebuild kit from Napa and other parts stores.
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Old Sep 4, 2009 | 03:00 PM
  #5  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

i found one vacume line that leaks which would be the one that leads to one of the sencers on the air intake would that be a problem? also i had my uncle come today and test my battery with his snapon load tester and when sitting there it showed it had 11.3 volts but when you hit the test button it only lit up one notch an the meter and it was the lowest one and it was in the red reading replace could this cause my car to run poorly like this?
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Old Sep 4, 2009 | 05:42 PM
  #6  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

replaced the battery that wasnt it. i figured out the vacume line that was leaking was actualy broken in half and it goes up to a sencer that is in the air intake and it says ac on it which one is this? and i tryed to look and see how the injectors were spraying but i really couldent tell it was hard to see but i did notice when i turned the car off that when i removed the electrical plugs from the top of the injectors that the top side of the drivers side injector looked wet? could that mean it needs new orings in there? if not should they both be like that?
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Old Sep 4, 2009 | 07:32 PM
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Re: 88 tbi running rough...

Yeah, I figured a low battery likely wouldn't be the root of your trouble. Go ahead and get that vacuum line fixed. ANY vacuum line that's leaking can potentially cause a rough idle. Usually the bigger the leak, the worse the idle. If the EGR valve is stuck open, that can also cause a major vacuum loss, especially at idle. As far as checking the injectors, looking at the spray pattern is usually how I go about it. You could take some brake parts cleaner and spray off the top of them, then blow them dry with compressed air, then run the motor again and see they're wet on top again. If so, maybe you do have leaky injectors. Keep in mind though, that the crankcase vapors come through the air cleaner from the tube in the passenger side valve cover, so it could just be motor oil on them. Either way, clean them off and see if they get wet again. Btw, if that sensor you're referring to that says AC on it is on the air cleaner horn, it just controls a flapper door in the air cleaner horn so that the motor will draw warm air off the exhaust manifold until the motor warms up. When I put headers on mine, which don't have the heat stove for that, I just put a vacuum cap/plug over the nipple on the throttle body where that vacuum hose goes. So either plug that vacuum port or fix the line. Of course a general tune-up is always a good idea too (fuel filter, spark plugs, cap, rotor, and plug wires if they're really old). That's about all I really know to suggest for now. Of course, if you can borrow a code scanner, you ought to see if there's any trouble codes stored in the computer. Sometimes that'll help point you in the right direction for diagnosing things.
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Old Sep 5, 2009 | 12:33 AM
  #8  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

i will try some of the things you suggested and see how it goes i just changed the plugs wires fuel filter cap and rotor and now the battery so its not any of them the sencer im referring to is on the pass side under the airfilter cover and the liquid on the injectors im pretty sure is gas because it dosent look like oil and is only there right after i start it. i will start it again tomarrow and try to see how theyre spraying
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Old Sep 5, 2009 | 04:59 AM
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From: Roy,UT USA
Re: 88 tbi running rough...

Ok, I think I'm on the right track about which "sensor" it is you're referring to. If it's the one that has a couple of heater hoses going to it, that's the cutoff valve for the heater core. When the A/C is turned on it shuts off coolant flow to the heater core so that the A/C blows colder. The vacuum line moves a valve up and down inside it. If it is gas like you say on top of the injectors, then something's gotta be leaking on the throttle body. Could be injector o-rings, a gasket, or maybe the fuel pressure regulator diaphragm. All of that stuff comes in the general rebuild kit from the parts store.
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Old Sep 5, 2009 | 05:31 AM
  #10  
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From: Toledo, Ohio
Car: 91' bird(WS6>>305TBI), 82'Regal
Re: 88 tbi running rough...

Originally Posted by polaris91
the sencer im referring to is on the pass side under the airfilter cover
The sensor(s) on the PASS. side that you may be referring to for the 305TBI(LO3) will either be the IAC > (Idle Air Control) OR the TPS >(Throttle Postion Sensor) Both will effect drivability/Idle greatly! >> I have the same Engine.....

Last edited by bitchin_buick; Sep 5, 2009 at 05:35 AM. Reason: forgot stuff!
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Old Sep 5, 2009 | 06:18 AM
  #11  
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From: Roy,UT USA
Re: 88 tbi running rough...

Originally Posted by bitchin_buick
The sensor(s) on the PASS. side that you may be referring to for the 305TBI(LO3) will either be the IAC > (Idle Air Control) OR the TPS >(Throttle Postion Sensor) Both will effect drivability/Idle greatly! >> I have the same Engine.....
He said the "sensor" has a vacuum line running to it, so that's why I'm guessing it's the heater core cutoff valve, which isn't a sensor anyways. The only true sensor I can think of that employs a vacuum line would be the MAP sensor up on the firewall cowling.
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Old Sep 5, 2009 | 06:23 AM
  #12  
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From: Toledo, Ohio
Car: 91' bird(WS6>>305TBI), 82'Regal
Re: 88 tbi running rough...

Originally Posted by Pat Hall
He said the "sensor" has a vacuum line running to it, so that's why I'm guessing it's the heater core cutoff valve, which isn't a sensor anyways. The only true sensor I can think of that employs a vacuum line would be the MAP sensor up on the firewall cowling.
ooops! I should read a little more carefully! Any how, If you plan to keep the car wouldn't hurt to change the TPS & IAC >>> both do effect drivability/Idle issues greatly >> both are on the Pass side for the LO3. Good luck!
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Old Sep 5, 2009 | 11:17 AM
  #13  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

well found out what the problem is now i need to know how to solve it the passanger side injector is not fireing at all no gas is coming out and i put a test light on the wires to see if it had power and i got no power on that side but i did on the other i also swapped the two connecters (drivers to pass) and the pass side started working but the drivers stopped so does anybody know what could be causing this i diddnt see any broken wires
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Old Sep 5, 2009 | 01:34 PM
  #14  
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Re: 88 tbi running rough...

Just noticed in your VIDEO it looked like the Charge Gauge was reading 10VDC and didn't respond to your throttle increase.

IS your alternator OK?
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Old Sep 5, 2009 | 02:02 PM
  #15  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

i belive it is i will bring it to advanced auto and get it checked tomarrow though i figured out what the problem was the *&$^@#g idiot that i bought the car from removed the fuse for the #2 injector and the reason it ran good for a few days was because i hooked up some led lights inside the car and used the fuse box for power and what i stuck in there looked like a y so it connected both ports where the fuse would go were connected and that wire got pulled out and i diddnt realise it so it stopped powering the injector
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Old Sep 7, 2009 | 02:41 AM
  #16  
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From: Roy,UT USA
Re: 88 tbi running rough...

Hey, good job on finding the problem! Yeah, that's definitely not the fuse you'd wanna pull out to use for a power source.
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Old Sep 7, 2009 | 10:35 AM
  #17  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

i diddnt even pull it out it was already missing when i tryed to use it the po of this car was an idiot
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Old Sep 8, 2009 | 05:35 PM
  #18  
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From: Roy,UT USA
Re: 88 tbi running rough...

Originally Posted by polaris91
i diddnt even pull it out it was already missing when i tryed to use it the po of this car was an idiot
Yeah, anybody that'd remove one of the injector driver fuses and leave it out is obviously not playing with a full deck! Lol.
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Old Sep 8, 2009 | 07:55 PM
  #19  
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From: bridgeport ny
Car: 88 camaro z28
Engine: 305
Re: 88 tbi running rough...

seeing how its now finished i figured ide post up some pics the only thing left to do is sterio

http://s161.photobucket.com/albums/t...risrd7/camaro/
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