C5 barely runs after car wash

[b757captain]

Greetings from the sandbox,

I just picked up an '04 freshly imported from the states. My first day of ownership ended with a barely running car, messages include reduced engine power, service traction control, service active handling, and a host of trouble codes. I pulled the codes (thanks to this site for that!) and the relevant ones seem to be 0120, 0220, and 1516.

Here's what happened: I drove the car home and stopped for gas and a wash. I thought the car wash would be safe (one of those gantry thingys where the car doesn't move, the washer does). While I'm sitting, jets of water start spraying up from underneath (to clean the undercarriage, presumably). I didn't know about the "auto bidet" until it was too late, but I can always remember that I have done stupider things in the past, and will do even stupider things in the future!! As I exited the station, all the above mentioned actions take place, and I can do maybe 30 mph tops. In UAE traffic this is like inviting a crowd to your impending funeral!

After researching (this site again!) I've come to the hopeful conclusion that maybe I've got a bad chassis ground. The codes all point to problems with the TPS and throttle pedal sensors, and since the old girl was running perfectly at first I can't see any relevance other than maybe water spray soaking the (TAC??) located under the battery.

I did check the interior fuse panel area and the carpet was damp, and I could see a small amount of moisture around the fuse panel, though not the computer next to it. I left everything open overnight to dry out, which it did. Now I can get 1600 RPM and a smooth idle (day before only 1100 and bad idle) but all warnings still present.

Another question/possibility: I have noticed over here that the gasoline has a much harsher and stronger smell, leading me to believe that the gas here is refined much differently. Since the troubles started just about as long as it takes for the fresh fuel to mix through the system, could this have had any bearing on my problems? I know the computer can detect high/low octane, but would "strange" gasoline cause any problems?

I'm off to the local dealer today to see just how far over I'm going to be bent, but can anyone offer any other insights?

Many thanks,

Mark

 

[XLR8]

Mark, I'm afraid I can offer no insight as to the cause of your issues but hopefully someone will come along soon with useful suggestions.

The best I can do is commiserate with you and welcome you to our site.
Good luck with a speedy recovery!
Jane Ann

 

[gmjunkie]

First thing I'd Check is the ALL Chassis grounds!!

#6 Under the brake booster on top of frame!
#7 On top of frame behind Left Hood Henge!!(Several wires,Gang connection) Remove from frame take apart and clean!!
#8 On top of frame behind Right Hood Henge!!(Several wires,Gang connection) Remove from frame take apart and clean!!
#9 Under battery on top of frame 2-3 wires!

#6,7,8 and 9 are extremely critical!!The rest are too,but with the problems your having,they'd be the first thing I'd check!!

 

[Patrick]

Another question/possibility: I have noticed over here that the gasoline has a much harsher and stronger smell, leading me to believe that the gas here is refined much differently. Since the troubles started just about as long as it takes for the fresh fuel to mix through the system, could this have had any bearing on my problems? I know the computer can detect high/low octane, but would "strange" gasoline cause any problems?

Mark,
I'm thinking this is likely unrelated to your electrical woes, but I suspect you're onto something when you mention the gasoline is probably refined a bit differently over there. We not only have federal regulations on automotive fuel, but individual sellers of gasoline will often add detergents into the gas to keep the fuel injectors clean.

Do you have access to Techron as an additive?


-Patrick

 

[Hib Halverson]

The gasoline in the UAE is not an issue unless it's leaded fuel, has a problem with water content, or is of an octane below 87 R+M/2. If you have a problem with the first two problems, you need to drain the car's fuel tanks and refill with new gasoline. Also, if it's the first problem, leaded fuel has destroyed the car's cats and O2Ses. They'll need to be replaced. If it's the third problem, drive the car really easy for a while to use up some of the gas then go look for some 100 octane unleaded racing gas and fill-up.

As for the DTCs set, I'm traveling without access to my FSMs.

My guess is the problem is not fuel it all but that chassis wash got some electrical connection wet.

First thing I'd do is check the chassis grounds that are accessible. Then I'd pull the battery and look at the ECM connections. If you got the car used, there's always the possibility that somone disconnected then improperly reconnected something in a way that disturbed the connecter's "watertightness".

As it's hot over there in the UAE, park the thing in the sun with the hood open and hope the heat eventually vaporizes the offending moisture.

 

[b757captain]

Thanks for all the replys -

The relevant codes are:

0120 - Throttle/Pedal Position Sensor/Switch "A" Circuit
0220 - Throttle Position Sensor Circuit
1516 - Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
Also 1278, but that shows as the traction control inhibited due to the other problems

I took the car to the dealer this morning and the got it right in. Two hours later they say it's fixed. Cool, I say, what did they find - I was told they "cleaned things". Language can be a barrier here! Go out to the car, and nothing is fixed. All problems still there. When I go back in and tell the service writer he hooks me up with the tech, who tells me he thinks its a ground. Of course, I'm trying not to let the steam coming from my ears show, and I refrained asking why he drove the car out of the shop the first time saying it was repaired when it obviously wasn't. So it's still there with no word as of this evening.

The bad thing is that I could have tested all the grounds myself, but at the moment I have no tools and no place to work on the car. Even so I still could have had answers faster doing it myself. Live and learn, all part of expat living.

I think all the fuel here is unleaded, but there's no telling for sure - the pumps don't say. I'm just trying to work out all the coincidences. I did fill with Premium, or as it's called here, Super (reg unleaded is called Special). Weirdly enough, the pump handle for Super is green. I did a double take and actually told the pump guy I wanted to smell the fuel before it went into my car, seeing as I'm used to green in the US being diesel. He looked at me like I was from Mars! Don't even get me started on the list of gas station rules and etiquette here, but don't attempt to just find an open spot at a pump! Get in line (or the "que") or they will - politely - redirect you the next spot in line. Can't pump your own gas, but I did fill an empty tank, 17 gals, for 70 DHS. $19 US.

I will take another trek to the shop tomorrow (Sunday here is Monday everywhere else. Another weird local thing), hopefully with better news.

Again, thanks for all the help!

Mark

 

[caseyk]

Car Wash Woes

The same thing happened to me,like an idiot :W I decided I wanted to wash my motor at the car wash,after I was done,I cranked it up and when I did,the car freaked out! I had every code known to man come up on the car ,I think the car even made up some codes on it's own! I was riding down the road right after my ingenious wash job and the anti lock brakes were engaging for no reason.I was switching lanes without a choice.The next day ,everything was fine,no codes,no nothing.I would imagine that my ground points need cleaning,but I know for sure that after I washed the motor,everything freaked out.That's my two cents.

 

[caseyk]

I did get reduced engine power on the DIC and it was running really bad.I also got shocks inoperable,service traction control,service ABS soon, and the list goes on.I have a hard time believing it was the gas,The LS1 likes it hot,dry and corrosion free LOL!!!

 

[b757captain]

I know better than to wash the engine - I cut my teeth (so to speak) on a C4 '85 TPI. Finally sold it with 193,000 miles on it and I did just about all the work on it myself. Learned a lot about how GM computer engineers think. I'm learning all over again that the basic lessons about good grounds have not been learned yet!

I just picked up the car from the dealer here, everything all good, she's running fine. I didn't even ask what they did, I'll go out later and peek under the hood. I definitely plan to replace those ground connector modules with a soldered eyelet set, though. They look like a never-ending nightmare.

Plenty hot here, though surprisingly enough, it gets quite pleasant in the late fall and winter. Temps in the mid-70s, chilly overnights. It's about as humid a when I lived in Miami, though. Summers at 120F and 60% humidity and salt air means corrosion is going to be an ongoing concern.

Again, many thanks to all suggestions. Now on to the next question: the cartridge for the 12 disc CD changer is missing. Is this a standard off-the-shelf item any stereo shop would carry, or a GM specific item that I'll have to order?

Thanks,

Mark

 

[LLC5]

I would be concerned about the moisture by the fuse panel unless you know for sure how it got there, water in this area can create all sorts of electrical nightmares. Make sure your evaporator drain tube isn't plugged.

 

[pitiful]

Mark i have the same problem,threw much trail and error that wet carpet by your fuse box was what cause my problems.Same mo error codes upon error codes and making them up.In my case there was a large pigtail of wires growing threw the firewall behind the battery,There was a rubber gromit around these wires which was not correctly positioned around the wires.Unforunitly i had to burn a few bucks uselessly at the local dealership myself,hope this helps. Pit

 

[Toms007]

Pitiful, welcome to CAC. Not trying to scold you or anything, but you do realize that this thread is a year and a half old don't you? You input is very welcomed, but hopefully Mark got his problem fixed a long time ago.