Vacuum & other things - 1996 Eldorado - Page 3
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 3 of 4 FirstFirst 1 2 3 4 LastLast
Results 31 to 45 of 51
Cadillac Seville / Cadillac Eldorado Forum Discussion, Vacuum & other things - 1996 Eldorado in Past Cadillac Vehicle Discussion; thanks sub, here's what today brought: changed the two ckp's, pita to get to the screws, the upper one is ...
  1. #31
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    thanks sub, here's what today brought:

    changed the two ckp's, pita to get to the screws, the upper one is a bit easier to get to, since you may get there through a hole in the exhaust manifold, small ratchet, long extension and the angle thingy (forgot the name). cleared codes, tried to fire up, nothing...

    figured that one of the cables broke again... to make a long story (8.30am to 5.00pm) short, re-wired the whole thing (sensors to icm) and also bought a new plug for one of the sensors, since one wire broke too close to the plug. now everything is soldered, should last more time than quick connectors. started to play around with the connecting possibilities (btw you were right sub, the sensors were connected the way around). if i connected both sensors wouldn't start, with just one (no matter in which position) would start crappy one way, a tad better the other. well, at one point i got to a configuration that would fire right up and also make the tach work. almost yelled out loud of happiness. so things were messed up a lot and fortunately i got it figured out and it works now!

    remaining issues regarding engine at this point:

    change the ckp connector plug at the icm (since it is too loose and doesn't get contact, and also bending pins doesn't help anymore)

    check idle system, since it says it's idling too high, maybe because of vacuum leak(s), for sure there is one at the explosion valve

    one of the o2 sensors has bad wiring and is shorted, today i saw the first time that the car is running amazingly rich (black-grey smoke on acceleration). is it normal that the pcm makes it run rich like that while signal from o2 sensors is absent?

    now the funny thing: made an involuntary oil change when i forgot to mount back the oil filter adapter and fired her up. 5 seconds and like 5 quarts were gone, fortunately had a pan down there...

  2. #32
    Submariner409's Avatar
    Submariner409 is offline If it won't run, stick on fender vents
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    75
    Posts
    45,981

    Re: vacuum & other things

    Whoa !!!!!!!! - As you found out, without much resistance that little oil pump moves a fearsome amount of oil !

    Track down the vacuum leaks and clean the throttlebody and Idle Control.

  3. #33
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    it certainly does get to pump something, high performance

    just put back the intake plenum, the backfire valve seems to be fine now, more or less. couldn't get the o-ring, so i "welded" the flap-body onto the plenum. i'm not sure whether it's the flap itself that still whistles or the power steering pump. flap looked good, so i just cleaned it out. also when i smoke into that area it doesn't get sucked nowhere. maybe i just get a new one, like a month delivery time or so and not so expensive. or a plenum from the junkyard, i'll think about it...

    it's running a tad better now, but only well on wot, with little gas it stutters. found also that one cable of one injector is broke inside the plug, but still making contact. will change that anyways these days.

    now the interesting part: on 3 cylinders there's only intermittent spark, and one has good spark at idle, but it gets less while accelerating.

    what would you guess, wires or coils (would be 3 of them)? wires are ac delco and look good... changed plugs already, looked all ok. also changed icm (not new but both, the old and the new one have the same behavior).

  4. #34
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    running fine so far, but...

    when i clear codes it runs a bit funny (hesitating mild acceleration, fine wot) until it sets P0152 (high voltage o2 sensor bank 2 sensor 1, the one i fixed the burned cables at). after setting the code it runs fine, open loop i suppose. still has the spark issue, although i changed the plug wires and also one of the supposedly bad coils. what happens is that at idle it seems to miss some sparks (checked with test light), but only at bank 1. opening the throttle a bit it misses all sparks on some cylinders. now i was thinking that maybe it switches off cylinders on purpose, is this an 8-6-4 engine? performance-wise i couldn't complain at this point. anybody got an idea on what might be going on? i'm running out of things to check...

  5. #35
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,803

    Re: vacuum & other things

    No, it is not an 8-6-4 engine. Maybe a bad coil?

  6. #36
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    thanks ranger, good to know and be able to exclude that.

    don't think it's a bad coil, since 5 of them (4 old and one new) would be bad, too unlikely. wires and plugs are changed also.

    i think i'll skip the ignition issue for now and go step by step regarding the pcm codes.

    what the car does is run crappy if i clean codes. after a while P0152 appears (front o2 sensor high voltage) and the car runs fine, no rough idle, nothing. didn't check mileage thoroughly but more or less should end up at 14mpg in town. probably not so good, gonna take her on the highway this weekend i think, just to check. had also the general misfire code once (P0300), but didn't come back yet.

    also checked for vacuum leaks with break cleaner, couldn't find any. don't get the point of my testlight showing intermittent spark at the rear bank and lots of sparks at the front bank when the car is idling and accelerating just fine... i guess i'll upload a video on it, for better explanation. however, the high voltage on the o2 sensor tells me that it is bad and should be changed? or what could cause it? funny also, it's the bank with a lot of sparks... just confusing, does anybody have an idea?

    read around a lot on this today and there was a thread in another forum on a 2000 DTS i think, same issues, turned out to be ckp's, but mine are new, wouldn't think they could still be failing (ac delco).

    well, hopefully somebody has a clue on these issues. thanks guys, already have been a great help!

  7. #37
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,803

    Re: vacuum & other things

    I wonder if that O2 sensor is bad, sending erroneous info to the PCM and it in return is either leaning or enriching the injector pulse width.

    What did you mean by "fixed the burned cables" in post #34?

  8. #38
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    the harness going to that sensor got melted (including plug, partially) by having come too close to the exhaust manifold. so what happened was that i got the p0151 (low voltage) at that sensor, because of the short circuit and therefore no signal from sensor to pcm. so what i did is cut off these cables and put them back together as they are supposed to be. not proud of how i did it, since because of lack of space i just twisted and isolated... however, that sensor is now giving the high voltage, which means rich combustion.

    and you're right, until it detects the sensor sending wrong signals it leans out fuel-air mixture and that might lead to engine running crappy at idle and part throttle. wot is open loop anyways if i'm not wrong, and therefore it runs good. and i'd say this has nothing to do with the spark issue...

    thinking about it i'll re-wire that circuit partially to rule out poor results of me improvising things. then we'll see what comes up regarding that sensor sending high voltage. if it still does i might wanna change it.

    one question though: does the grounding of the heating circuit for that (and the other) sensor(s) go to the rear left engine corner? i have a orange 12awg cable there that has been cut and only a black 20awg cable connects to it, twisted... no clue right now where that black cable goes to, if i'd take a guess i'd say rear bank o2 sensor, but i really don't know yet, it disappears between engine and tranny.

  9. #39
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,803

    Re: vacuum & other things

    I think your problem may be the O2 sensor wire splice. I remember ewill3rd (a caddy tech) once mention that you cannot splice or solder them. I think he said there is a special kit that has to be used. You might find it with some searching by going to his profile and searching his posts. It was several years ago as I recall. Your best bet might be to replace that wire if you can.

  10. #40
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    i guess i found the thread you mention:

    click

    sounds to me as if i'm gonna have to take care of this first and make sure the wiring is as consistent as possible. sounds strange though that the cable itself is used as some sort of "air channel". but since the issue is not with the wires that are part of the sensor but the engine harness it makes sense anyways to do it right instead of just twisting cables together. will have to find a different place to do that repair, since there is no space where the wires melted.

  11. #41
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,803

    Re: vacuum & other things

    Yup, that's it. Not sure I fully understand it either, but what the hell do I know. Might be better to just replace that wire with the factory connectors on either end. I know that may be easier said than done though.

  12. #42
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    sounds actually more imaginable what sub says in that thread, the wire portion from the sensor to the plug is critical and i'd say the clean air reference should be going through that wire, since the plug anyways interrupts airflow (and the air near the sensor and near the pcm are pretty much the same, that's for sure). i'll buy the heat shrink thingies mentioned by ewill3rd to make sure everything is the way it's supposed to be.
    still think that the sensor is probably bad, since the dtc is "high voltage", bad wiring normally leads to "low voltage". i'll keep you posted on that (and everything else hehe).

    you guys and this forum have been of great help, thanks again!

    if by tomorrow the clutch puller i ordered at az arrives (stuck in customs) this weekend i'll go for the a/c compressor and change coil + clutch assembly, since somebody broke a pin at the clutch coil trying to get the plug off...

  13. #43
    Submariner409's Avatar
    Submariner409 is offline If it won't run, stick on fender vents
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    75
    Posts
    45,981

    Re: Whistling pressure relief on N* Intake Manifold???

    It's not "air" as such. It's a calibrated electrical resistance/capacitance circuit - impedance - which supplies the base line against which the variable O2 sensor signal is measured.

    The sensor changes electrical conductivity depending on the oxygen content of the exhaust gas. The "clean air reference" load allows precise measurement of that changing electrical output.

    JimD would have a better electrical explanation than I.

  14. #44
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106
    Thread Starter

    Re: vacuum & other things

    yeah, i remember having heard that during mechanic's school back then

    just that i don't think the air travels all the way to the pcm, back and forth, not with the plug in the middle at least. i remember that the early sensors (1 cable) took air (oxygen) reference through small holes at the sensor housing or at the top where the cable goes to the sensor. with the here discussed sensors it might be the cable insulation that leaves space for air going through, but only up to the plug. that's what i think at least, would have to take a really close look on the sensor, cables and plug to figure out where it gets this reference from.

    point is that i think the engine harness itself pretty sure may be soldered etc., only the sensor cables not, to avoid changing properties like impedance and also to not alter the probable air reference mechanism. what also seems important here is that you'd want to respect cable length and diameter, so it won't affect resistance and impedance much, speaking of the whole circuit.

    we'll see how it works out in my case, gonna use the connectors with heat shrink as recommended in the other thread and come back with results.

    last night i was thinking about the spark again and there it was: the enlightenment.

    when the rear bank spark is intermittent and the front bank spark strong and fine then it must have to do something with the post-coil system, say cable, plug, ground. cables new, plugs new. also have been interchanging cables at one moment to figure out if that was the issue. known good cable also gave intermittent spark.

    the thing here is the system: waste spark ignition. no way the coil could transform voltage at one tower only. that's what came to me at that moment. probably pretty obvious, but for me important to diagnose and haven't thought of it that way yet.

    will do some checks on that, i highly suspect grounding issues for the rear bank.

    sorry to mix up things here a bit for being fighting at two fronts at a time...

  15. #45
    Submariner409's Avatar
    Submariner409 is offline If it won't run, stick on fender vents
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    75
    Posts
    45,981

    Re: Whistling pressure relief on N* Intake Manifold???

    Have you seen this spark plug cable routing diagram - which coil tower to which plug ?

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