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Discussion Starter #1
I bought a 90 DeVille (4.5 liter) last year with 88,000 miles on it. It seemed to be idling rough, so I did a tune-up. I changed the plugs, wires, dist cap, rotor, fuel filter and air filter. Shortly thereafter (around 93,000 miles) the engine developed a constant misfire on one cylinder. I pulled that plug, and it was sparking, so I assumed it was an injector problem. I had no more problems with it until this April, when it developed that same type of constant misfire again.
This time I took it to my family's mechanic (worked for Cadillac 20+ years, so I trust his opinion), and he determined two injectors were out of range, so I had them replaced. He said the rest of the injectors were OK and in the range of resistance. Now, last monday, I hit a huge pothole (love these Indiana roads!) and when i stop at the next light, the darn misfire was back again!! I drove home and the next morning when I left, the engine was running fine (whew). Then, on Wednesday morning, it was back to running poorly again, and now last night (Thursday) it started running properly again. I don't want to take it in and have more injectors replaced, when I don't think that is the problem, but I cant figure this one out.
The engine currently has 118,000 miles on it, and the PCM is throwing a code P46 (Left/Right bank fuel discrepancy), which it has been since the first time this happened. Also, when making right turns, the engine bogs down when low on fuel (6 gallons or under). This has been getting progressively worse over the last year and a half, it used to only bog down under 3 gallons. Maybe fuel pump/pressure regulator?? Any input you might have would be great. I just dont want to keep throwing money away fixing problems that arent broken.

Thanks,
Joe
 

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2005 CTS-V, 1994 Infiniti Q45
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Joe... Welcome aboard.... Thanks for signing up..... WOOHOO, a new Indiana cadillac member... Its about time!!! :D

Anyway, it does sound like an injector problem..... My recommendation to you would be to get your injectors cleaned at the dealer, or a compitent shop. Ask for a pressurized fuel rail flush.....

Id also check your fuel pump.....

Regarding the right turns, thats a super common problem, and its the design of the gas tank..... You need to get a new gas tank and it would be a good idea to replace the pump too...... Something like $250 for the tank/pump I think......
 

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Discussion Starter #3
Thanks for the reply, Wes. Glad to see another hoosier on the board here... so are there a lot of us that frequent the forums?

Well, knock on wood, I haven't had anymore problems since last week, but I mostly drove my girlfriend's car all weekend so who knows? I don't doubt there is an injector problem, but I just found it strange that this problem would show up again after hitting the mother of all potholes. I could understand if I screwed up the front-end or suspension, but an injector? LOL

I plan on getting the tank/pump changed when I get some extra money after the holidays (if it lasts that long), so hopefully that will clear up these problems.


Thanks
Joe
 

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2005 CTS-V, 1994 Infiniti Q45
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I bet it will..... Personally, if at all possible, its not worth the wait...... A bad pump could cause damage to other things....... You can take a chance, but I wouldnt......

Unfortunately, there arent really any other regular hoosiers here.... :( Im about the only one..... Theres a few from Chicagoland, Ohio area, Tenessee, etc..... Most of the guys here (the regulars anyway) seem to be from the east coast...... Let me know if you'd be interested in meeting sometime...... Email me at [email protected] , there is a meet this weekend Im going to in Louisville!!!
 
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