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Bad Gas Cap?

23K views 85 replies 14 participants last post by  Xocticz 
#1 ·
So the wife was driving our 'new' SRX and had this happen, it was like the power steering went out and came back, then the check engine and trac control light came on. it then stalled. check engine light would stay on. She could start it but then it would stall out again. So I went to go get her and I took the gas cap off and put it back on, not pushing, but until it clicked a bunch of times. I got it home, and then took it to work and it ran okay, still have the check engine light on, but would a bad gas cap make ALL those things happen?
 
#30 ·
I would get the engine cover off and then inspect every line you can find. If you can remove a line, test it with a vacuum pump or low pressure. Look for bolts or clamps holding mating surfaces together and with engine running, spray liberally with WD-40 to see if it gets sucked in where the two parts join. It's tedious but I know no other way.
 
#32 ·
If it did it would probably be a first. You don't feel lucky?
 
#33 ·
It is common for the DSM guys to pressurize the intake system looking for boost leaks, way easier to hear when the engine is off.


Will putting 10-20 PSI on the intake hurt anything?

I can't see it hurting anything at that pressure but I wonder if it would get to the right places under pressure not vacuum, hook up a vacuum pump or brake bleeder maybe with engine off.

We use Home Depot to build the cap and just put it on the turbo inlet, works awesome.
 
#35 ·
Okay so this is getting interesting. Yesterday we hopped in to go to coldwater for a family thanksgiving thing, and no warning lights at all. Great, I think, today should be a good day! When I was getting on the highway I clicked on the cruise (it was in the off position) and when I hit to set it, nothing happened. So I looked down and had engine and trac lights on, which weren't on when I was turning to get on the offramp, I looked. Okay...maybe something is up in the steering column. It ran 'okay' the rest of the way there but when I'd let off the gas it would noticeably 'clunk' like it wasn't running quite right, so I'd use the sport shift to down shift and that helped a bit. We get into coldwater and whenever I'd turn the wheel I'd feel a 'grab' for just a real quick second, nothing to affect driving. We turn onto their road and it stalls. I coast to the side and restart it. Now I just have the engine light and it gets to their house. It was at this point I was going to check the oil and when I popped the hood I notice that the dealership never re-secured the engine cover from when they had it last weekend. So I check the oil (about halfway in the safe area, so I'm using it a little bit it seems) and put the cover back in place. We go to the store for them later, just an engine light, and then coming out of the store, no warning lights. Last night driving home I let off the gas and the engine light comes on but that's it the rest of the way, I don't touch the cruise. I had to come into work this morning and when I'm coming up to turn into work, the left turn signal doesn't work at all, until after I turn left then it's fine.

What a weird vehicle. :)
 
#36 ·
Good attitude, now get your new codes read and report, please.
 
#38 ·
I've got an Actron that will read and erase,show freeze frame, history and live monitoring. Got it from Advance Auto, as I recall, near $200 +/-
 
#40 ·
so I don't have a reader yet, and not sure what timeframe it'll be before I get one, but I like playing the 'what the heck is it game', so I'll throw out the throttle body possibility. Could the timing of hitting the gas, or letting up on it with a gunked up TB possibly cause it to toss errors out there? it seems my p2119, p2135, p2176 issues might be related to that, or that the TB is bad, seems I've read that GM had issues with them for some time.
 
#41 ·
DTC P2119
Circuit Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2. If the ECM detects the throttle valve did not return to the rest position within a calibrated time, this DTC sets.
DTC P2176
Circuit Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the throttle actuator control (TAC) motor. The ECM monitors the actual throttle valve position using throttle position (TP) sensor 1 and 2. If the ECM detects that TP sensor 1 and 2 voltages are not within a specified range during the throttle learn procedure or the throttle learn procedure is not learned after an ECM replacement, this DTC sets.
DTC P2138
Circuit Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted in the pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to the position of the accelerator pedal. The engine control module (ECM) supplies a separate 5-volt reference and low reference circuit for each of the APP sensors.

The APP sensor 1 signal voltage increases as the pedal is depressed, from approximately 1 volt at rest to above 4 volts when fully depressed. The APP sensor 2 signal voltage increases as the pedal is depressed, from approximately 0.5 volts at rest to more than 2 volts with the accelerator pedal fully depressed.

If the ECM detects that the difference between APP sensor 1 and 2 signal voltage is more than a predetermined value, this DTC sets.

Couldn't find P2135 so I did 38.
 
#43 ·
making sure you go in and see the dealer.
Right!

Do some checking and cleaning then erase the codes. They may not come back. Also, most of these codes are saying that things are not as expected so if car is running OK it's no big deal.
 
#44 ·
well out on the road the car decided to go into limp mode. about 15 minutes later I was able to get it started with just the check engine light and get it to the dealership, so no tow charges, but I had mentioned things for him to look at, so we'll see from there.
 
#47 ·
Well, to be honest it's kind of running out. Although the dealer here has been pretty nice about giving me info. He gave me all the printouts of every warranty work claim done to the car, which showed that both cats have been changed, and one of the head gaskets was changed as well. It just makes me think that the dealership in lansing, mi got it running as good as they could to get rid of it, which to me would be against their certified used program.
 
#48 ·
If a Caddy dealer sold a 2004 CPO certified pre-owned, I would be very surprised, even if the mileage was low. It is too old. Some used vehicles only come with 90 day warranties if the factory warranty (ies) have expired. These short term used car warranties vary so much state to state (law) that I could not speculate whether you are in a position to have the parts and labor covered by the dealer.

I am not mechanically inclined. If the problem has persisted after (just) one trip back to the dealer (Sept. 14 was it?). If I was going to have the same (selling) dealer fix it on my dime, I'd leave the SRX with the dealer for a couple of weeks and let them experience the symptoms (and codes) first hand and iron this out before returning the vehicle to me (you).

Remember, all dealerships (and their service techs) are not created equal. Do you think that your dealership is up to it? I am not suggesting you changes horses quite yet. But if they can't properly diagnose the issue(s) and then fix them without merely throwing parts at it until the symptoms and codes go away, then I would consider another dealership.

I am going to have to go back and read your posts back from the beginning.

PJ
 
#49 ·
I would think it was certified pre owned as I had the 3k/3 month powertrain warranty given to me from cadillac.

I gave him some ideas, especially throttle body as it seems that those are issues with 2004ish SRXs. He seems pretty good actually, having it and looking it over for a few days and not finding anything, pulling all the codes and then not charging me.
 
#50 ·
so it seems I have a Borg Caddy. Fixed itself again while at the dealership after sitting over thanksgiving. Pulled these codes: P2176, C0242,C0244,C0461, C0561, U1000, U1016, P0101, P1101, P0068, P0171, P0174, P2119, P2135 which seem to be pretty much the same ones. Now, I don't know if they really don't know what's up or just don't want to dig into it that much. I asked if the throttle body or some intake imbalance could pop these codes and cause limp mode.
 
#51 ·
Sheep, have you ever dug into finding a vacuum leak downstream of the throttle body, especially the ribbed connector to the manifold? Also, have you tried wiggling all the major module connectors on and near the engine? You've got a vacuum leak and communication problems which are easy to correct if you take the time.

I suspect, if you did get a warranty, the dealer likely thinks he won't get paid enough to spend the time looking. My offer still stands.
 
#52 ·
No I didn't look really. Call me lazy. No really, go ahead. If I would trust the thing to make that trip I might take you up on the offer. They still have it for another day or 2, maybe it'll go wrong for them while driving it, but really, isn't that what the codes are for anyway?

edit: and downstream meaning from the engine back to the airbox? would a vaccuum leak in the airbox itself be an issue? also, what a pita to change the air filter. geez.
 
#53 ·
Your leak is likely in the area indicated.

Auto part Steering part Automotive window part Automotive fuel system Transmission part
 
#54 ·
"Not leaning any way in general really just yet, there are various things we check to see if it has been under water it does not appear that this was a flood vehicle."

is what I got from my guy at the dealership. Sooo..since he has all those codes wouldn't you think he could lean one way or another? or is he basically not wanting to work on it?
 
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