Runs Good Cold, Bad Hot
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Joined: Aug 2008
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From: Bay Area Californina
Runs Good Cold, Bad Hot
Hey everybody! I have an 85 that is completely stock that i have been working on for a few months. Finally got it running afer sitting for 15 years! My problem is that when it is cold it runs pretty good, however after about 4 minutes or so of warming up when i give it gas it feels like it is missing, or not running smooth, same when i am under acceleration. When i step on it, it does not feel so bad its just at lower rpms. I have done all the basic tune up stuff like plugs, wires, rotor, cap, cleaned the MAF and IAC. Any suggestions? Still not positive if the IAC is working after cleaning the MAF,TB and IAC it feels the same. It holds fuel pressure around 32 psi and goes up a little with RPMs. Any suggestions would be great!
Thanks
Brian
Thanks
Brian
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Setting for 15 years...that thing must be mint!
Check the Throttle Body Sensor voltage setting, have the ICM tested, clean or change the O2 sensor. Distributor coil is good or new? Timing set right? Check Vader's site for a good write up on the IAC set up/install.
Check the Throttle Body Sensor voltage setting, have the ICM tested, clean or change the O2 sensor. Distributor coil is good or new? Timing set right? Check Vader's site for a good write up on the IAC set up/install.
Intermediate
Joined: May 2008
Posts: 38
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From: Yuba City CA
My c4 car sat from 1994 until this year. I found that the injectors screens were clogged. I also ended up putting a kit in the fuel regulator. I own an ultrasonic cleaner and was able to clean reuse the injectors. This solved the problem nicely. In my case, I had no other codes to deal with.
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Joined: Aug 2008
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From: Bay Area Californina
thanks for the info.. im not sure if it is throwing any codes, i really need to get my hands on a tester and find out. Is there any tricks to check codes without a tester? Eagle 1147; thanks for the ideas on what to check, ill try testing one at a time and see what i can find out. djoksch; was it easy to get to the injector screens?
Thanks
Brian
Thanks
Brian
3rd Gear
Joined: Oct 2007
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32 lbs is not enough pressure. At least for my 86. I was getting 32 lbs and the thing was terrible. Installed new fuel pump and all problems solved. You should be getting 42-45 lbs i believe. Correct me if i'm wrong anyone.
Le Mans Master
Joined: Oct 2006
Posts: 6,842
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From: Palmdale CA
thanks for the info.. im not sure if it is throwing any codes, i really need to get my hands on a tester and find out. Is there any tricks to check codes without a tester? Eagle 1147; thanks for the ideas on what to check, ill try testing one at a time and see what i can find out. djoksch; was it easy to get to the injector screens?
Thanks
Brian
Thanks
Brian
You don't need a tester to get the codes. The car will give them to you. All you have to do is put a wire between two terminals on an easy-to-get-to connector under the dash. I believe it is the A and B terminal. Do this with the ignition off and then turn the ignition all the way to on. The "Service Engine Soon" light or SES light on the dash will flash a 'welcome code' of 12 three times. You'll see it flash once, then pause then twice (that's 12) with a long pause in between each set. After that, it'll start flashing the codes and it will flash them in order, three times each, with a pause in between each.
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Joined: Aug 2008
Posts: 62
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From: Bay Area Californina
Thats great! thanks for the info...Sounds like it will be no problem, i will check what codes i have, if any, and post them to the thread! At least this will give me a starting point on what needs replacing!
Unfortunatly after 15 years of sitting it is not mint
i got it from a family member who drove it hard in its early years...
great info
Brian
Unfortunatly after 15 years of sitting it is not mint
i got it from a family member who drove it hard in its early years...great info
Brian
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Thread Starter
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Joined: Aug 2008
Posts: 62
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From: Bay Area Californina
Yeah thats another item i have been considering, there just so damn expensive for a set of good ones im trying to make sure thats the problem befor i jump into it. Ive been reading there is a resistance test that can be performed when they are cold and hot... I need to give that a shot!
Thanks
Thanks
