Deville 94 4.9 p030 rough idle stalling backfire
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 15 of 20
Cadillac DeVille 1985 to 2005 including:
1985-1992 Fleetwood, 1993 Sixty Special, All FWD Forum Discussion, Deville 94 4.9 p030 rough idle stalling backfire in Past Cadillac Vehicle Discussion; Happy 4th of July everyone! I hope you all had a good Independence Day! Now on to bad news. Ok ...
  1. #1
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Deville 94 4.9 p030 rough idle stalling backfire

    Happy 4th of July everyone!
    I hope you all had a good Independence Day!

    Now on to bad news.

    Ok so my car finally has got really bad.
    I keep getting the p030 code.

    Last night from work it had a real bad problem.
    She would get up to around 10 mph and be slow moving and was almost stalling out. She really struggled to get up to 20 mph. It got so bad that when I went to floor the pedal it would still hesitate and would not move it kept trying while this happen the check engine light came on along with p030 as current.

    Once it got to 25 mph I would floor it to try and get it to go and then suddenly it would surge forward and have a hard time.

    Is this the isc motor?

    I tried to start it this morning it was rough starting. It actually did not start I held the key for a good 5 seconds and it sounded way different.
    Then when I tried a second time it started but stalled the moment I gave it the gas it would not go on it's own power dash was on and everything engine was dead though.
    3rd time it started up but like last night having a hard time getting at 10 mph felt like it could stop at any time drove around the block and let it sit.

    Put a new isc motor it starts but it took 3 times and it backfires and when I go to push the gas it, it just seems to want to die it almost stops when I give it the gas

    One time it just went out.

    Lately it's been turning over harder.
    I'll hold the key down for 3 to 5 seconds before it kicks on.

    Before it was right away.

    Could it be besides the isc the catalytic converter? A fuel filter or maybe a cam sensor?
    Are any of those easy to replace? If I can't get it fixed tomorrow evening I am taking it to a garage. Going to have it towed on a flat bed to a garage if it's not the ics.

    I may have a faulty isc motor I bought it clicks after each time I shut off the engine my old one has done it before but only once I know about.

    ----------

    Another thing I noticed on my information panel on the left side of the dash about avg mpg etc
    The range I was suppose to be getting has dropped drastically from what it started out as ever since yesterday with in accordance with the problem at hand.

    One thing I've also noticed in the past 3 weeks give or take that my fuel gauge is not always right about like one min it maybe 13 gallon left and maybe later on it might be 12 or suddenly 11 it may jump back up.
    Usually it's not a problem and hardly happens but it does some times oddly.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Ranger's Avatar
    Ranger is online now Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,781

    Re: Cadillac deville 94 4.9 v8 p030 rough idle stalling backfire you name it!

    Forget the ISC motor. As the name implies, it controls idle speed. When you are driving, the throttle is WAAAY off idle.

    Start by checking your fuel pressure.

  4. #3
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Cadillac deville 94 4.9 v8 p030 rough idle stalling backfire you name it!

    Thanks Ranger.

    I'll put the old isc on later.
    I'll be checking the fuel pressure shortly.
    I was told by a mechanic it maybe the fuel pump needs replaced.
    So it could very much be the problem.

    Tell me do you know where the map aka mass air flow sensor is located on my caddy? I was told to disconnect it and try to see how it runs without it because it may need to replaced.

    Also do you have a photo or a forum that has a picture where the air flow sensor is that I need to unplug?

    Thanks again!

  5. #4
    Ranger's Avatar
    Ranger is online now Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,781

    Re: Cadillac deville 94 4.9 v8 p030 rough idle stalling backfire you name it!

    Pretty sure the 4.9 does not have a MAF sensor.

    MAP sensor is #1


  6. #5
    MoistCabbage's Avatar
    MoistCabbage is online now Cadillac Owners 10000+ Posts
    Automobile(s): Crimson 2001 Seville STS, 1990 Seville (RIP)
    Join Date
    Sep 2010
    Location
    East Boston MA.
    Age
    26
    Posts
    20,830
    Correct, no MAF.

  7. #6
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Cadillac deville 94 4.9 v8 p030 rough idle stalling backfire you name it!

    Yeah I forgot the diagram was on the engine hood. It showed the map sensor.

    Sadly it's the fuel pump I'm almost positive.

    Before my not working air ride pump kicks on I can hear what a sounds like a pump on the drivers side by the gas tank try to kick on and engage. It usually takes a second and the moment I put the keys in the ignition I am good to go. Not this time.

    I'm putting on the old isc motor tonight and having it towed to the garage and wait it out till the person can work on it Monday.

  8. #7
    Ranger's Avatar
    Ranger is online now Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,781

    Re: Cadillac deville 94 4.9 v8 p030 rough idle stalling backfire you name it!

    Quote Originally Posted by CaptainAmericaUSA View Post
    Sadly it's the fuel pump I'm almost positive.
    I'm leaning strongly in that direction as well.

  9. #8
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    Does $600 sound right for a mechanic to drop the gas tank and put in a new pump? Plus $80 for diagnostic fee? Or should I go else where?

  10. #9
    Ranger's Avatar
    Ranger is online now Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,781

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    Probably not out of line at todays prices. Shop around and compare, but I'd demand that the diagnostic fee be deducted from the price if he does the job. I think that is pretty standard practice.

  11. #10
    MoistCabbage's Avatar
    MoistCabbage is online now Cadillac Owners 10000+ Posts
    Automobile(s): Crimson 2001 Seville STS, 1990 Seville (RIP)
    Join Date
    Sep 2010
    Location
    East Boston MA.
    Age
    26
    Posts
    20,830
    That's high, and the brand of fuel pump will make a big difference.

    The most expensive fuel pump in Rockauto is $265. If he marked that up to $300, that leaves 3 hour labor at $100 per hour. It won't take that long, and I'm assuming he's cheaper.

  12. #11
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    He told me he don't buy that Auto Zone crap because he don't want to have to take it out in two weeks to replace it. So hopefully he is not lying.

  13. #12
    MoistCabbage's Avatar
    MoistCabbage is online now Cadillac Owners 10000+ Posts
    Automobile(s): Crimson 2001 Seville STS, 1990 Seville (RIP)
    Join Date
    Sep 2010
    Location
    East Boston MA.
    Age
    26
    Posts
    20,830
    The OEM AC Delco pump is less than $200, and there are several other good brands even cheaper than that, including Airtex, which in many cases, is a reboxed OEM part.

    He's still overcharging for labor, a lot.

    A few months back, my mother had a new Delphi pump assembly, AND a new fuel tank installed for ~$600, parts and labor.

  14. #13
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    Yeah I just want it fixed and hopefully that's the problem price is really overpriced.
    I'll tell him I want the gas tank replaced as well for that price since mine is rusted.

  15. #14
    Ranger's Avatar
    Ranger is online now Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    72,781

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    Quote Originally Posted by CaptainAmericaUSA View Post
    He told me he don't buy that Auto Zone crap because he don't want to have to take it out in two weeks to replace it. So hopefully he is not lying.
    He gets points for that.

  16. #15
    CaptainAmericaUSA is offline Cadillac Owners Member
    Automobile(s): Devillie 94 4.9L V&
    Join Date
    May 2013
    Posts
    27

    Re: Deville 94 4.9 p030 rough idle stalling backfire

    $797.00 total.

    It's the fuel pump.

    So much for $680.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting