2008 Aveo, auto trans, went into "limp mode" not allowing acceleration over 10km/hr.

[OliviaRose]

Good day: I find myself in a sticky situation. Two days ago I fired up my 2008 Aveo and while it did start, the engine sounded absolutely horrible. I mean REALLY horrible. But it kept running so I took a chance and tried to get to my mechanic's shop which is quite close by. The car would not accelerate over 10km/hr: it was a nightmare. Made it to the shop and fortunately he was there. He heard the engine and came out to see what was making the unholy racket. Hi: me again, says I. He rummaged in the engine in a spot right in front of the passenger front seat and said that's where the defective part is located. He retrieved a diagnostic thingy that he plugged into the car somewhere and managed to get it backed out onto the road where he drove it about for a very short while. LOTS of very loud engine revving happening. LOTS of really fast forwards and reverses. And quite quickly the engine sounded normal again. So he popped by with my car and we chatted while it idled beautifully. The tool thingy he plugged into my car recalibrated it or something close to that. I can't recall the name of the part but he informed me it will cost about $300.00 just for the part. And he told me that his diagnostic tool informed him that my car had been running in "limp mode". I believe the part it needs has something to do with a choke? Or fuel regulation? I was pretty upset as I can't afford a more expensive car at this point so my memory of the part name disappeared very quickly. Plus the mechanic suggested I drive it off a cliff....But the theory of it seems to me to be related to the automatic choke function of the car and the function of controlling the idle/fuel supply rate while the thing is running. I hope I'm explaining this at least half way clearly. And this afternoon when I cautiously fired it up it seemed to me to be idling much faster than it used to (pre-limp phase). However, it did allow me to pick up groceries this afternoon for which I am thankful. One odd thing I noticed after my mechanic had messed with it and did his temporary fix was that the automatic transmission gear shifting was a lot smoother than pre-limp phase. Odd but true and quite noticeable for me to have picked up on it. So my question is: 2008 Aveo, 158,000km, I drive less than 2000km per year. My mechanic does not think it's worth repairing. I'm stuck as a car is necessary where we live (no public transit) and I don't know what to do. I'm retired and have limited funds for a different car. My mechanic doesn't want me to keep throwing money at it. So is it worth repairing? And does anyone have any experience with this particular issue? I've never had a limp car before. Check engine light has been on and off (mostly on) for years; clock doesn't work 99% of the time (haha) so we figured it was just an electrical glitch. There is a kill-switch on the battery that is working brilliantly for over a year now as something will drain the battery if I didn't drive it for a few days (which is my normal rate of driving). So cheaper for the kill-switch than trying to find the electric short and I'm happy with it. So, here I sit feeling pretty tense trying to decide what to do. I'm inclined to have the repair done so at least I can sell it or hopefully drive it for a while longer. Help!!!
Best regards

[sjcleckley1]

What was the code possible throttle body or air leak or like I said what are the codes I Had a 2008 had no money also but I have some god given skills and tools was able to work on it my self and drove it 480,000 miles had to replace the trans at 380,000 pion bearing was shot there are a few things that should on a car belts hoses and water pump timing belt wheel bearings be regular maintained for my self I bought an autel MaxiAp 200 for 35.00 there 60.00 now but a good investment you can read codes program keys and see live data it's bluetooth so you need a smartphone also but worth while and if you want to find the circuit that causing the drain disconnect the battery and then put a small light bulb between the battery post and terminal connector you might have to play with the wattage and pull fuses/relay it will get dimmer when you have eliminated a circuit that is using power unless you have a amp meter I had no problems with battery drain but had my instrument lights and right side running and tail lights go out and that was a bad connection in the buss connection in the fuse box in the engine compartment right side about 2 inches long sort of milky color standing if front of car but left if setting in car

See if you find out the codes

Also when you disconnect the battery you reset/clear/zero all learned values Throttle Body Crank Position Sensor Fuel Trim and when started after a battery disconnect/reconnect buy letting it idle till the radiator fan comes then putting it in every gear for say 30 seconds back to neutral/park the do that again with the AC on from my experience my car was not that bad it was not paying attention to things in fact I bought another one 2009 Pontiac G3

Things that you will replace wheel bearings alternator belts and tensioner timing belt and componets

[OliviaRose]

Yes, I stopped by my mechanic's shop yesterday and he was closed for the day so I'll try again when I have a chance. Interesting about the battery disconnect reset: I do recall being told that earlier but can't recall what the problem was at the time.... The AC doesn't work; there's a leak somewhere. My mechanic filled it and had it running for about 20 - 25 minutes on a horribly hot day. He dropped the car off at my place and I took it out: the AC worked for about 3 minutes. A cruel outcome on such a hot hot day! So not worth looking for the leak. I use the sun roof a lot and I love it. I will do what you recommend about letting it idle and putting it in every gear for say 30 seconds back to neutral/park the do that again with the AC on. I don't think it's a bad car at all, I've had to do very little work to it over the years. I might have owned it for as long as 10 yr now, maybe a bit less. I'll forward your comments to my mechanic for his information. I received good advice on this forum with regard to rapid door lock recycling and it was repaired and has never happened again. Had to replace the power steering belt so far and buy a new battery (before the kill switch was installed), fix the door lock rapid recycling issue and tires but that all seems to me to be normal wear and tear on a 2008 car. I don't have a cell phone at this point so can't do your test using one. At this point, one week after the car went into limp mode, it's been starting and running very well. As I mentioned earlier, the gears are changing much more smoothly than before my mechanic did whatever it was he did to it to get it out of limp mode. He reset something from what I've been reading online. I read that I should check the fluid levels: oil and transmission fluid so I'll do that. I'll try and get the codes from him and let you know. Thanks so very much for your help! Talk to you again.

[OliviaRose]

Hello again: I was able to visit my mechanic at his shop and he couldn't recall the code that was showing during the time it was in limp mode as that was about 2 weeks ago now. But he took the car out for a bit of a run and came back pleased with how it's running now. The check engine light is on again so I asked him to find out why and the code showed an "O2" so he told me not to bother with it or worry about it. It certainly is running remarkably better than it was prior to going into limp mode and the reset he did on it. There was an issue today with the kill switch affecting the battery charging (I can't tell you how though) so he changed it out to a new one and apparently that helped the battery charging somehow. I was banished to sit in the car while he was working on it: I think I ask too many questions.... then one of the turning signals failed on my way to see him, so he fixed that for me as well. A productive appointment all 'round and no charge! I've joined the provincial auto association in case I need a tow or the car breaks down when I'm not on the island I live on and I've purchased a small flip phone (for seniors) just in case of emergencies while I'm driving. So at this point the car is running very well, the engine light is showing off and on, I have a new battery kill switch and fobs plus a new turning signal lightbulb. He also had topped up the oil and transmission fluids at some point so no need for an oil change. It's never burned oil since I've owned it and I think I'm the second owner. I didn't have a chance to ask about flushing the transmission fluid after the limp mode incident. I've read that that can be a good idea. He did talk me out of purchasing a new-to-me used car as this car isn't costing me very much in repairs each year yet and it is running well. I did ask about the reset that happens when the kill switch is activated and how that might affect what caused the limp mode but he wasn't able to answer me properly as I hadn't written down the code or name of the problem at the time (2 weeks ago).
Are you able to give me some, or one, suggestion for dealing with the non functioning A/C? I could certainly use it as I have a older dog that requires transport to the vet clinic sometimes in the hot weather and he cannot tolerate hot weather at all. My mechanic has recharged the system but it didn't last longer than about 20 - 30 minutes. So it seems there's a leak in the system. Any suggestions for helping fix that would be wonderful and very much appreciated.
Thank you once again for your earlier reply,
Cheers!

[sjcleckley1]

Well they can put some UV die in it to help find the leak but could be the O rings where the hoses bolt on to the compressor condenser, evaporator where it goes into the cab, hoses (my truck did that once after not using it 2 years) compressor or leaking condenser or evaporator just about everywhere but usually where joints seal

You could buy a can of freon install it and then spray everything with soapy water and see if anything bubbles otherwise it's going to be up to a AC person and someone needs to check the pressures

My daughter had a older Honda Accord that AC wasn't working pressures were ok but got weirder when it got hot but worked good cold engine but as it got hot as it got hot AC did not work scratched my head a while the person that looked at it said it need a new compressor quoted her like a $1000 (called my crying to drive to her and check it 350 miles round trip DAD) but pressures were higher to high when hot finally it came to me and found that the gate/valve for the heater was stuck full open servo motor to control it was broken seems the Aveo has blend door no valve at least haven't found one as the temp control panel has cables what an AC does compress the freon and high pressure it makes heat (stores energy could be 250 psi depends on outside temp) goes through the condensing coil front of radiator (keep that clean of bugs dirt etc. as reduces the efficiency) gets rid of heat and turns gas to liquid then that goes through a restriction (expansion valve or orifice) and the liquid expands loses energy low pressure (could be 50 psi) and the liquid turns to gas and gets cold in the evaporator coil. Basically you are moving heat from the cab and moving it outside and you are picking up cold from outside you heard of a heat pump same just it has valves and works backwards in winter you have an optimum charge or correct amount of freon to work properly sometimes the restriction gets clogged and then you will have to much pressure on the low side

And they also pull a vacuum on a system to remove air and moisture before filling a new or repaired system probably find a good AC guy to find the leak

I got long winded on this one

[OliviaRose]

Whew! Lots of new information for me. Many thanks for taking the time to craft a detailed and informative reply to my query. I live in a very small community on a small island, so no A/C guys in the 'hood. And after reading your reply it does sound like that's what I'd have to do: take it to a good A/C guy. I guess it's another hot summer coming up for me. But I will mention the soapy water test and O rings and the rest of the things noted in your first paragraph to my mechanic. I doubt I can afford an A/C guy if my mechanic can't find the issue(s) fairly easily. That's life, isn't it? And by the way, you're a great DAD.

[sjcleckley1]

Forgot to mention I had to replace the throttle body once check engine light came on and would surge as you were driving it slow down speed up it was under waranty but the dealer was milking me said had to pay a 100 diagnostic fee and then they said my plugs were the wrong ones and throttle body need to be cleaned so I said I do all that my self on the work order the said my tires were low on presaaure like 25 psi whitch was a lie as I checked the as soon as I got and preassure was what I run them 34 front and 32 rear put the recomended plugs and cleaned the throttle body no change had a long conversation and they replaced the throttle body and fixed the problem I have a hard time taking my stuff to other so called mechanics
I also had the cat plug up and would not go over 55 without cutting out then got down to 5 on the way home

Also had a sticking valve once started miss firing on the way to work had low compression in 1 cylinder took of the intake hose and ran the motor revving it up and sprayed a whole can of berrymans carb cleaner into the intake fixed it but once in a while you could hear it slam shut when motor was turned off you need to run some cleaner through the fuel system once in a while it finaly quite doing it