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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?
 
#56 ·
And, of course, as it sits at the dealership they've said it starts and runs fine. *sigh*. So I'm probably going to pick it up in the next day or 2 and spend time after work every night just tracking down potential vacuum issues. however I'll probably buy a reader that can clear codes because I wonder if that's what enables it to 'reset' so it runs okay for a while.
 
#57 ·
This makes no sense, for them it runs fine but it's full of DTCs and they won't fix that? You might want to consider Michigan lemon law. See how they respond to that.
 
#59 ·
#61 ·
Yep, it'll do that.
 
#62 ·
Okay this is getting awesome. I pick it up from the dealer cuz why not? He tells me since they wiped the codes they haven't had an issue. sure enough it runs fine. so we get in and head home, switch cars into the caddy and head off to get the scanner. I have to hit the gas at an intersection to get into traffic and when I let off the gas boom, lights and it stalls going down the road. I take it in neutral and put it back in gear, still rolling and it starts up and continues on. I get into the advanced parking lot and seems fine. the guy does a free scan and I get the 6 common codes so I go in and buy the scanner and we head home. runs fine going home but I have an engine light and trac control. get in the driveway and run the scanner, same codes. I clear them out and it runs fine. I pump the gas and it stalls. P2135 is the only code it's throwing. I clear it twice, and do the same thing and it comes back. Dirty/bad throttle body maybe?
 
#63 ·
P2135 is a correlation problem between the 2 throttle position sensors in the throttle body. The diagnostic is mostly about poor connections in the wiring harness. My suggestion, as silly as it might sound, is to wiggle the connectors at the throttle body and at the ECM and see what happens. This DTC can shut down the engine.
 
#65 ·
Update: I decided to change my oil today, was at 7% usage and I don't like those monitors much anyway. After changing I wiggle some wires around the TB and then go on an errand. It runs poorly the whole way. Engine light, trac light most of the way and surging stuttering. I stop at where Im' going, clear codes which are the throttle pos. ones, and then head back, same thing surging/stuttering. I get home and decide I'm going to clean the TB. I pull off the hose and it looks brand new in there. Nothing at all. So I put it back on and start it up, seems to run fine. I go around and wiggle all the connectors, no changes. I do however get 2 codes (no engine light) of p1101 and p0101.
 
#66 ·
Po101 is the important one. Here are the physical cause possibilities ;

Inspect for the following conditions:
• A restricted or collapsed air intake duct
• A misaligned air intake duct
• A dirty or deteriorating air filter element
• Any objects blocking the air inlet screen of the mass air flow (MAF)/intake air temperature (IAT) sensor
• Any contamination or debris on the sensing elements of the MAF/IAT sensor
• Any water intrusion in the induction system
• Any vacuum leak downstream of the MAF/IAT sensor
• Any type of restriction in the exhaust system-.
• Inspect the harness of the MAF sensor to verify that it is not routed too close to the following components:
- Any aftermarket accessories-
- The ignition coils
- Any solenoids
- Any relays
- Any motors

The MAF readings are not as expected in the software is what the code means. It takes 2 ignition cycles to turn on the check engine light.
 
#67 · (Edited)
ah. Well hopefully I might have solved my issue. I noticed when I pulled the maf sensor off that the gasket is old. it's a rubber doodad but it's all stretched out and not good looking. makes me wonder if they actually changed the maf sensor when they said they did. So I put everything together nice and tight (one of the screws was loose by hand) and took it out and beat the crap out of it. nary a code. Nada. runs great. so we'll see after sitting overnight what happens. However, do not go to cole gilmore cadillac in kalamazoo/portage if that's all it took to fix this thing.

edit: So drove it in today, no issues again. Kind of makes me mad about all the crap I've gone thru but I guess 'do it yourself' is probably the best bet. Now, do they sell MAF sensor gaskets by themselves? I can't seem to find one. And if they come with the MAF sensor, then that kinda points to 'they didn't change it the last time'. Thanks for all the help glake, you are supremely awesome.
 
#68 ·
See how simple it is? Only 66 posts to fix a problem! :highfive:
 
#69 ·
They're baaaaaaaaaaaaaack. P1101 and P0101 last night when the wife was driving, so I cleared them out and they set again coming into work. I did have a nice 2 weeks to the day of driving however. I wonder if the bolt backed itself out of the hole considering how loose it was when I found it. I'll check tonight.
 
#70 ·
Okay, so I go out at lunch and check the bolt, nice & snug. check all the connections and everything feels nice & tight. go driving around, no problem. decide to punch it and bam engine light and trac control, and get 2 P2135 codes for the throttle position sensor. It idles fine after that but let off the gas and it clunks pretty hard. I am, obviously, at a loss. take the hose and maf sensor back off and reseat?
 
#71 ·
Reading the diagnostic in the SERVICE MANUAL, 3 pages, you will find the most likely cause is in wiring and connections. A little detective work on them might lead to a fix. This code is not related to the MAF. I think you cured that.
 
#72 ·
Yea I'm wondering if it's the connection to the throttle body, I've read on other threads that it can get 'loose' in cold weather shrinkage, and judging from how that TB looked when I took the hose off, it makes me think they've tried to fix it before. It was quite shiny.
 
#74 ·
Well it kept kinda throwing codes at me so when I got home I figured I'd pull the plug on the TB and see what it looked like. Looked like there was some old dielectric grease on it, but not much. that was a mistake. it is not sitting at a tractor & engine parking lot because it won't stay running. Oops. so I'm buying some dielectric grease tomorrow and see if I can get it going.
 
#75 ·
Get some electrical contact cleaner first. Then carefully slightly crimp the female metal part of the connector for better contact.
 
#76 ·
Well, I went out this morning, and my order of operation was:
1) tap on sensor/tps area, try to start. runs like crap.
2) put dielectric grease on contacts, starts and runs, but like crap.
3) pull hose off and flip the TB flap. runs like a charm.

so I think what happens is, over the course of 2ish weeks, the sensor gets 'out of calibration' and by flipping it you zero it out?
 
#77 ·
Well after doing a little 90ish mile trip each way for a funeral, it didn't take long for me to get lights and for it to start running rough, so I pulled over and did the whole 'flip the flipper' and it's running fine again.

Were all these TBs built overseas or for the lowest bidder or something? I see quite a few people complaining about them.
 
#78 ·
So it's been a while since I've had any issues (and I still haven't since my last post) but it got me to wondering. Is it a heat thing? It's been cold here in michigan and I haven't had any issues, and I'm wondering if the TBs are really sensitive to heat. It's going to be warming up a bit here in MI for the next few days (40s/50s) so I guess I'll find out if that's an issue.
 
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