Hard start when warm, strange idle
#1
Hard start when warm, strange idle
Hey all -
Love the forums. So much great information here. Thanks to everyone who takes the time to help diagnose problems!
That said, I've got a problem of my own in need of diagnosis. I think I know what the problem could be, but I'd like another opinion. Lately, the car (a 2001 2.7T) has been tough to start at times when warm, requiring a bit of time to cool down before it will start again. This doesn't happen all the time, but is getting a bit more common. If I drive for awhile, turn off the car for a short period of time, then come back, it's tough to start. It cranks fine, just doesn't fire. Plus, as I'm cranking it, I smell a hefty odor of gas, almost like the car is flooded.
In addition, the car is idling strange at times. Intermittent, but it occasionally idles quite high (around 1200-1400 RPM), and this seems to often go hand in hand with the starting problems. Today, it was idling like this, revving up and down, and when I went from R to D, it stalled out. I was able to get it to start again, but then turned the car off and it had trouble starting.
There are two things that I know need to be replaced in the car: Coolant temp sensor (this is what I think the problem is...am I right?) and a Bypass valve. If it is the ECT, is it a pretty easy DIY?
Thanks!
Love the forums. So much great information here. Thanks to everyone who takes the time to help diagnose problems!
That said, I've got a problem of my own in need of diagnosis. I think I know what the problem could be, but I'd like another opinion. Lately, the car (a 2001 2.7T) has been tough to start at times when warm, requiring a bit of time to cool down before it will start again. This doesn't happen all the time, but is getting a bit more common. If I drive for awhile, turn off the car for a short period of time, then come back, it's tough to start. It cranks fine, just doesn't fire. Plus, as I'm cranking it, I smell a hefty odor of gas, almost like the car is flooded.
In addition, the car is idling strange at times. Intermittent, but it occasionally idles quite high (around 1200-1400 RPM), and this seems to often go hand in hand with the starting problems. Today, it was idling like this, revving up and down, and when I went from R to D, it stalled out. I was able to get it to start again, but then turned the car off and it had trouble starting.
There are two things that I know need to be replaced in the car: Coolant temp sensor (this is what I think the problem is...am I right?) and a Bypass valve. If it is the ECT, is it a pretty easy DIY?
Thanks!
#3
RE: Hard start when warm, strange idle
My 99 2.8 has been having the hard start problem when warm. I am going to replace the coolant temp sensor, but I woul like to know what it looks like, where it is located, and the degree of dificulty todo the job, as well as how much should I expect to pay for the part ?
#5
RE: Hard start when warm, strange idle
Sounds like coolant temp sensor. I had the same problem as you. I changed my CTS and problem vanished.
For carlos: on the 2.8 it's located on the passenger side of the engine near the firewall. It'll be sticking straight up. You'll see a plug connected right on top it. In order to get to it (and see if for that matter) you'll need to remove your MAF hose. I went ahead and removed the airbox, MAF, and hose just to have the extra room just in case.
You can get the part at the dealer for around $28 - $40 depeding on your dealer. Make sure to buy a new O-ring. It's a pretty easy install.
For carlos: on the 2.8 it's located on the passenger side of the engine near the firewall. It'll be sticking straight up. You'll see a plug connected right on top it. In order to get to it (and see if for that matter) you'll need to remove your MAF hose. I went ahead and removed the airbox, MAF, and hose just to have the extra room just in case.
You can get the part at the dealer for around $28 - $40 depeding on your dealer. Make sure to buy a new O-ring. It's a pretty easy install.
#6
RE: Hard start when warm, strange idle
Go here: http://www.ecstuning.com/stage/edpd/...ategory=Engine
Scroll down to OEM coolant temp sensor to see what it looks like. Make sure to select the proper color sensor.
Scroll down to OEM coolant temp sensor to see what it looks like. Make sure to select the proper color sensor.
#7
RE: Hard start when warm, strange idle
Cool. I figured it was the temp sensor. I just picked up a new one this afternoon, and I'm going to try to stick it in there in the next few days.
Does anyone have a guide for doing this on the 2.7T? I found it for other engine models, but not this one. I think it's underneath the MAF hose, slightly on the passenger side of the engine on the back - is that right?
Does anyone have a guide for doing this on the 2.7T? I found it for other engine models, but not this one. I think it's underneath the MAF hose, slightly on the passenger side of the engine on the back - is that right?
#8
RE: Hard start when warm, strange idle
I got the temp sensor at the dealer. I want to try to do the job myself. I looked on the fire wall behind the engine on the passanger side, and can't find anything that looks like the part I got which is a green conector witha gold pin on the top. I see3 relays right on the fire wall butI dont thinkany of them is the temp sensor.I assume it should be next to one of the radiator hoses, but the only thing I saw was in the front of the engine on the hose that comes out fron the bottom of the radiator.I own a 99 a6 quattro 2.8. Some of you guys said it was located towards the back. What are the chances of some one posting a diagram or a picture ?
Thanks
Thanks
#9
RE: Hard start when warm, strange idle
Did you remove the air hose going from the MAF into the back of the engine?
You won't see a color as far as when your looking for the identical part because its color will be masked by the plug that plugs into it. However, it will be sticking straight up and it's the only thing that has an electical plug to it. It's located low, near the firewall and is under the combi valve (silver, circularlooking valve closer to the top of the engine).
I'll see if i can find a pic for you.
You won't see a color as far as when your looking for the identical part because its color will be masked by the plug that plugs into it. However, it will be sticking straight up and it's the only thing that has an electical plug to it. It's located low, near the firewall and is under the combi valve (silver, circularlooking valve closer to the top of the engine).
I'll see if i can find a pic for you.