First check engine light - pissed!

Gallardos throw codes all the time. I wouldn't worry about it at all. It's most likely nothing.

 

Seems this is the common consensus on these cars. Hence why if you watch half the videos people post of driving their lambos around, you can usually see a CEL on their guage cluster.

Since it says O2 sensor. Try swapping the sensor with the other bank and see if the 6-10 bank light comes on. I get CELs all the time in the Diablo. I don't have cats though

Since it says O2 sensor. Try swapping the sensor with the other bank and see if the 6-10 bank light comes on. I get CELs all the time in the Diablo. I don't have cats though

 

 

That sounds awesome. If only I knew where the sensor was and how to get to it.

There may be a thread with pics on Lambo web if there is an exhaust repair/install section. Im not sure where they are on the G but I imagine they should be accessible from under the car

First don't worry to much about driving with check engine light on. 9 out 10 there is only a small issue if there was a real issue like a miss fire the check engine light will blink and the cat light will come on then its time to stop.

 

Normal with secondary are codes is the vacuum line to one of the valves is unplugged or the air pump hose that goes into the air box to the air pump is not connected.

 

It uses the o2 sensor to read the difference of air in the system when the air pump is on. If o2 sensor malfunctions you would also see o2 codes coming on.

 

Under each throttle body there is a metal diaphragm witch has a vacuum line to each one check to make sure they are plugged in exp. the valve on the right side but also check left one.

 

Depending on what year the car it is the hose that goes into the air cleaner to the air pump goes in from front on early cars and the back on later cars. Remove the right side air cleaner cap and the filter you can look into the housing and see if the hose is connected to the pump very common they don't get plugged back into the pump.

 

The miss fire tubes and sensor witch is not your issue, but I will give more info as some don't understand what they are.

 

The tubes go into the exhaust they send exhaust pulses to the sensor. The sensor sends the info to ecu at it compares that to the engine timing. If it reads a pulse out of time it reads this as a miss fire. The condensation forms in the tubes and the cats make water when cold. The water which can get into the tubes and blocks the exhaust pulses and the system thinks its a malfunction.

 

The early tubes where made from steal and can rust up. The new ones are stainless steal and don't rust but can still get water in them which can block the pulse until it gets hot and turns the water to vapor.

First don't worry to much about driving with check engine light on. 9 out 10 there is only a small issue if there was a real issue like a miss fire the check engine light will blink and the cat light will come on then its time to stop.

 

Normal with secondary are codes is the vacuum line to one of the valves is unplugged or the air pump hose that goes into the air box to the air pump is not connected.

 

It uses the o2 sensor to read the difference of air in the system when the air pump is on. If o2 sensor malfunctions you would also see o2 codes coming on.

 

Under each throttle body there is a metal diaphragm witch has a vacuum line to each one check to make sure they are plugged in exp. the valve on the right side but also check left one.

 

Depending on what year the car it is the hose that goes into the air cleaner to the air pump goes in from front on early cars and the back on later cars. Remove the right side air cleaner cap and the filter you can look into the housing and see if the hose is connected to the pump very common they don't get plugged back into the pump.

 

The miss fire tubes and sensor witch is not your issue, but I will give more info as some don't understand what they are.

 

The tubes go into the exhaust they send exhaust pulses to the sensor. The sensor sends the info to ecu at it compares that to the engine timing. If it reads a pulse out of time it reads this as a miss fire. The condensation forms in the tubes and the cats make water when cold. The water which can get into the tubes and blocks the exhaust pulses and the system thinks its a malfunction.

 

The early tubes where made from steal and can rust up. The new ones are stainless steal and don't rust but can still get water in them which can block the pulse until it gets hot and turns the water to vapor.

 

Hell of a response Jeff. The car is a 2008. Let me digest some of what you wrote and I'll post again.

 

Driving the car to dinner tonight to see if the CEL comes on again. If it does, I have a code reader and can reset it and then see if more driving around gets the tubes hot enough to vaporize the water and the CEL doesn't come back on. Hopefully this is the problem. I'm going to fill up too, and make sure the gas cap is tightened well.

 

If none of that works, I'll be trying the other suggestions (vacuum line to one of the valves or air pump hose) that Jeff mentioned above.

The code is just saying there is something wrong with the car....not specific. The code might or might not come back on, depending on what the problem is. I cleared one once and it came back after 100 miles. Turns out it was a slow leak in a line.

 

More than likely it's something small and easily fixed. If these things bother you, I will forwarn ou that they are more common than we'd like to see them.

 

Good luck man

Good start to the night tonight, bad ending. Need some advice.

 

 

Drove the car about 35 minutes to dinner and it was great. No issues. Fun drive.

 

Drove the car about 25 minutes and stopped for dessert. No issues. More fun.

 

 

Here's where the problems started. We finished dessert (about 15 minutes at the most) and I started the car. It sounded weird. Kind of a rough idle and it took a few minutes for it to get to normal 1000rpm (or thereabouts) range. I clicked it into 1st gear and started to drive - the car felt sluggish and just "off" in general. I accelerated through the parking lot (not hauling ass, just regular old leaving a parking lot) and once I hit about 4000rpm, the car abruptly stops accelerating and the RPMs drop hard. The car didn't stall, but it scared me so I lifted off the gas pedal a little and clicked 2nd gear. Super low RPM, weird sounding engine intake sucking noise. The car always seems to suck a lot of air at low RPM, and it's loud enough to hear as I drive through the neighborhood or a parking lot if I have the windows down. It's always done this. Is that weird?

 

Anyways, the car was lethargic, not wanting to accelerate with any pep, and the 1st gear 4000rpm accelerator stop thing happened again when I pulled away from a light about halfway home. Also, when I downshifted, the car didn't do the quick, responsive downshift with the throttle blip like it normally does - again, sluggish in general. Another thing - when I clicked both paddles to go into neutral as I approached a red light, the RPMs dropped waaaaay down to 500 or even a little less, and then went back up to the 1000 range.

 

In my neighborhood, there are a lot of speed bumps, and I remember one of the speed bumps I slowed way down since it's a little bigger than the others. As I was pulling away and accelerating after going over the bump, the car almost bucked like it would if it were a 6-speed and you didn't know how to use the clutch correctly.

 

I want to say it can't be the clutch, as it seems like the engine RPM issue is something else. But the weird shifting has me concerned about engine and clutch. I've only put 600 miles on the car since I bought it 5 weeks ago, and at the time of purchase, the clutch was 60% (verified by dealer and 3rd party PPI). Engine compression was perfect and everything else checked out fine over the course of an extensive 2-day PPI.

 

Could this be related to the CEL that I cleared a few days ago? Bad gas? Clutch? Something else?

 

Need help big time. I'm pissed!! lol

 

 

To make sure this is something that someone can make a direct answer to since my post above was longwinded, is the sucking noise from the engine when accelerating normal? If not, is that maybe a loose hose that could have possibly been the cause of the original CEL as well?

If your talking about the fans at the front of the car, yes this is normal when starting the car if the engine is warm. When starting the car from cold the fans come on as the engine heats up. I think I'm only aware of the fans when driving if I pull into a small space like a parking garage, but even then it's hard to tell over the engine.

 

 

 

Quote "The car always seems to suck a lot of air at low RPM, and it's loud enough to hear as I drive through the neighborhood or a parking lot if I have the windows down. It's always done this. Is that weird?"

Just remembered one more thing. I sat in the driveway for a second once I got home and was listening to the car to see if I heard anything that stood out. I hit the gas a couple of times and got the RPMs up to 5000 or so, and the car would rev up and then go all the way down to 500 or so, and then recover up to 1000rpm. On the 2nd or 3rd time doing it however, the car revved up and then went all the way down to nothing and died.

 

Here's the strange part: I started the car back up and it almost sounded normal again. I put it into first and pulled into the garage and as I pressed on the gas, it seemed to hook right up (unlike earlier) and I drove into the garage smoothly. What the fcuk???

If your talking about the fans at the front of the car, yes this is normal when starting the car if the engine is warm. When starting the car from cold the fans come on as the engine heats up. I think I'm only aware of the fans when driving if I pull into a small space like a parking garage, but even then it's hard to tell over the engine.

 

No, it's definitely not the fans. It's coming from behind me as I press the gas pedal, and sounds like air sucking into the intake or engine or something. It's pretty loud.

that is normal...drive with the windows down = it is a jet fighter with side intakes

 

No, it's definitely not the fans. It's coming from behind me as I press the gas pedal, and sounds like air sucking into the intake or engine or something. It's pretty loud.

 

that is normal...drive with the windows down = it is a jet fighter with side intakes

 

Okay that's a relief then. Thanks!

 

Any input on the other issues above?

Okay that's a relief then. Thanks!

 

Any input on the other issues above?

Just throwing it out there but if the car isn't driven much, the battery might be weak and any car can start acting really funky with a sluggish battery. Just thinking out loud...CEL could be coincidental to the battery or could be a seperate issue??

Some of these little units even let you read and adjust your mileage to your own liking!

Checked the airboxes and basically put my hands on every connector I could reach. Noticed I was a little low on oil, but that's it.

 

Any ideas? Bad gas? Sensor?

Dude you might want to take it in for service. It will lower your stress and ours You need some proper diagnostics done and if you keep this up that Y shaped vein in your forehead is going to pop.

Drove the car around the neighborhood this AM after I checked everything and it was fine. No accelerator lag, nothing weird.

 

Based on this it has to be a sensor right? Thoughts?

Can't answer that for sure but maybe. I can say though that the last thing you want is to have it lingering in the back of your mind the next time you take it out for a spirited run. Sometimes it's a good idea to spend a few hundred bucks for piece of mind.

 

 

Just spoke to a mechanic at Lambo Dallas and I'm going to plug the scanner back in and see if there are any pending codes. He said the P0491 was nothing to worry about, as it's fault on a system check and not a big deal unless it pops up more than once.

 

Still diagnosing this and hoping to find the solution this weekend.

Okay, just ran the scanner again and went for a gas-up and a drive.

 

No "pending" codes on the scanner. Filled up with gas.

 

Drove about 40 miles. Awesome. Nothing wrong. Car ran great.

 

WTF?

You should really sell your car...So far it's pissed you off twice! Once about the $1100 tune, and now a CEL.

 

I'll take it off your hands for $50k since it's such a lemon.

 

You should really sell your car...So far it's pissed you off twice! Once about the $1100 tune, and now a CEL.

 

I'll take it off your hands for $50k since it's such a lemon.

 

Great idea. Just PayPal me the $50k. I'll include free shipping since you're practically doing me a favor!