zxzkilme

What I mean by sometimes is that when I first start the car it will start no problem. Once I been driving the car for about 10-15 minutes I notice the temperature gauge will drop back from the middle back to cold then that's when I know that if i stall or turn the car off it wont start back up again unless i wait about 10-20 minutes. The stereo works when the car is off, the lights work too, and it also cranks. So it's not the battery. If I force the car to start when it won't, sometimes I get lucky and it will start, but it idles really high, around 1.7k rpms, but for the most part once I see the temperature gauge drop to cold when I'm driving then that's when I know the car wont start if I stall. No the engine is not cold because when I first start the engine during the day I know it's "cold" because I just started it, the temperature gauge will then go to the middle point of hot/cold and stay there for a bit, then after driving for about 10-15 minutes the temperature gauge drops back down to cold suddenly. What could be the problem?

ezone

The gauges you see in front of you, they get their data from the PCM. The PCM is transmitting its info to the gauges.

My guess: The PCM is receiving temperature data that is wrong, from the Engine Coolant Temperature sending unit.
You can confirm this by getting a basic scanner or code reader that can give some generic engine data from the computer. When the gauge drops, the computer data should agree with what you see on the gauge.

Replace the ECT sensor if the above is correct.

#17 if I picked the right car


http://www.hondaautomotiveparts.com/...SENSOR+%281%29



Use factory parts please.

zxzkilme

So it isn't a short in the ignition? Because why would an ect sensor cause the car not to start? Just curious. And would buying a new ect sensor fix the problem?

ezone

Nope.
And you don't understand what a "short" really is.


It causes flooding (overfueling).

Computer suddenly thinks the engine is something like -20* (or whatever false temp it really just erred to), and adds a crapton of extra fuel because that is what it it programmed to do for a cold engine. The sensor doesn't match the reality, the computer is just following orders. GIGO. (Google that if you don't know what it is.)
I pretty much told you how and why it can do this, at least the most common way it happens.
I told you what I would look for before wasting cash. I hate wasting cash.
Test, don't guess.
You can do a little testing and see if I am right before buying a sensor that can't be returned, or you can buy it and plug it in and see what happens.



Could be other things too. I can only guess from here.



"Factory parts are cheaper than cheapo parts that can't do the job, and pulling all your hair out trying to figure out why it's still broke after installing the cheapo parts."

zxzkilme

Lol, you're making more and more sense as you explain more. That explains why the car idles high when I force it to start and it does. Because it thinks the engine is cold causing the engine to idle at high rpms. Can I go to autozone or Kragen and get my ect sensor tested there?

ezone

Right. It might even be blowing black smoke out the tailpipe while it is acting up too.
Doubt it.
Is the CEL on?

If the problem hasn't set any codes, then you need live data.

If they only have the cheapest code reader they can get, there won't be any datastream from the PCM that you can use for diagnosis.


I would be driving with my scanner attached and reading live data. Drive until it acts badly then hit "record" (flight recorder). Then view the data at my leisure when I get back to the shop. (Really, I just read it on the road while driving. I don't do this in any traffic though, I have empty country roads to test drive on.)



Basically, if you have no codes then you must catch it in the act of failure. This means a scanner, and driving and waiting, watching.
Knowing a pattern where you can predict when it will act up helps a lot.


If it starts and runs and the gauge acts right when you check it, you will never find any problem at that point in time.

I don't make my money on wrong answers. I gotta be pretty dang certain something is going to solve a problem before I pull the trigger.

But I kinda would SWAG that your ECT is bad.

HTH

zxzkilme

yea CEL is on. Its actually been on before the problems began.

ezone

Oh jeez. That's the first clue.


Got any other handy information that you haven't bothered to mention?

zxzkilme

That's about it. I'm going to do more research to see if it's really the ect sensor that's causing the problem. Btw is there anyway to purposely run the car rich without having a bad ect? I notice my car pulls harder when i force my car to start when it won't. I can get over uphills better.

ezone

Don't bother. Just go get the codes read.
P0116
P0117
P0118
Are all ECT codes.

See what other codes are in there too.


Yes....but it is already programmed to do exactly that when the throttle is wide open.

Would going further than factory WOT enrichment programming make any significant gains? I have no idea, but I doubt it.

If you do it wrong, you can cost yourself a lot.

Matt_75

Really? ezone, the gentleman that's advising you for free I might add, is a Honda dealer technician who does his job better than most.

I'd recommend you listen and do what he says. He knows what he's talking about and can only help you if you provide accurate information and at least some details about your problem.

Good luck with that research to see if the ect is really your problem. ezone already told you more than once what to do.

This reminds me, as do many threads in here, of the old saying "You can lead a horse to water, but you can't make it drink."

ezone

+1, but the system won't let me.

zxzkilme

Well if it's the ECT for sure why should I get it checked? shouldn't I just buy a new one?

Matt_75

No one ever said it was the ECT for sure. ezone wanted you to prove it was the ECT based on the information he gave you. He likes to prove that a part is the problem and not just fire the parts cannon at it. He's asked you for the CEL codes. Did you get the codes read? If you don't want to answer his questions or get the codes then it's on you if you decide to replace the ECT without providing the necessary information to prove that the ECT is the problem.

ezone

You knew it was coming