What would make the ECM go into limp home mode?

The Yeti

The Yeti

Got 1000 hp?
Re: What would make the ECM go into limp home mode?

bezerk said:
i meant. the ecm goes into learning mode when you reinstall the ecm fuses. i was saying that once your engine is at operating temp. take fuses out for a few seconds, and reinstall them and maybe it will leanr it selve to be good.
also you need a scan tool to see what kind of values you have
Click to expand...

I'll try the fuse now, been fiddling with the truck since noon. Also, what scan tool is recommended?

Edit, removing fuse at operating temp makes no difference. Seems like it only relearns after a long time being disconnected.
Edit the edit: Grounds are great. Getting 14.43 volts anywhere with engine running.
 
midnightbluS10

midnightbluS10

Banned
Re: What would make the ECM go into limp home mode?

Datamaster is the recommended scantool. You can get it at www.ttspowersystems.com you'll need a cable for the laptop and it plugs into the same plug that scanners plug in to. The aldl port under the dash.
 
bezerk

bezerk

New member
Re: What would make the ECM go into limp home mode?

take out both fuses please. just to be sure.
 
The Yeti

The Yeti

Got 1000 hp?
Re: What would make the ECM go into limp home mode?

bezerk said:
take out both fuses please. just to be sure.
Click to expand...

I did both as you instructed. Wouldn't fire back up because it was still dumping fuel in so badly until I put the gas pedal to the floor and then continues to run excessivly rich.

A couple have said to check coolant temp switch, where is that located exactly and what is needed to check it (am I looking for certain voltages from it or what?)
 
GAShan

GAShan

Donating Member
Re: What would make the ECM go into limp home mode?

You need to get with Adam and Ian in Deltona. They're the closest to you that know their away around the trucks. I'm down iin Miami.
 
The Yeti

The Yeti

Got 1000 hp?
Re: What would make the ECM go into limp home mode?

Okay, heres the rundown since noon:
Drove the car to my shop and parked it until about 12. Worked on it a bit checking grounds and + wire to eliminate the possibility of shorts. Removed the ECM and access cover and traced back ribbon cable on it to switch and LED in cup holder- also noticed markings on chip (V5-50, suppose to be Phil Long for 50lb injectors). ECM is not origional and has SYCLONE written on it with sharpie. Removed ECMb and ECM1 fuse for most of the day as well as negative to battery so it would not be in limp mode but it must not have been enough time for it to reset. Removed both those fuses again after truck was running at proper temperature but still in limp mode. Gotta go home now, I will attempt to get an hour or so into working on it again tomorrow.
 
The Yeti

The Yeti

Got 1000 hp?
Re: What would make the ECM go into limp home mode?

GAShan said:
You need to get with Adam and Ian in Deltona. They're the closest to you that know their away around the trucks. I'm down iin Miami.
Click to expand...

What are their screen names or contact info. I'd love to get in touch with them. Thanks
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: What would make the ECM go into limp home mode?

Personally if it were me I would simply replace the ECM. This was one the very first issues I had with my TY and at the time I knew NOTHING about fuel injection. I took it to a guy here that deals with stuff like this and he replaced the ECM and all was well. It happened again to me about two years ago except it was intermittent. Swapped ECMs and all was well. If I am not mistaken code 55 is faulty ECM. I have yet to ever see this code set on a bad ECM. When your ECM goes bad the "rules" go out the window. If you plug in Datamaster I suspect you will find one of two things, one, everything looks semi normal and still runs like crap or two you will have very strange reading in strange places. Your CTS, in my opinion, will likely flash a code if it goes bad. You can easily tell if it is working when you hook Datamaster up. You can download the software free and use it 20 times. You will need an ALDL cable which you can make for about $20 or buy from $40 to $60 like Dig said. If I were you I would either replace the ECM or buy the cable next instead of tracking this and that down. You're going to waste a lot of time.
 
midnightbluS10

midnightbluS10

Banned
Re: What would make the ECM go into limp home mode?

I believe you can check the CTS with an ohmeter. You'd need the specs for comparison. We were actually talking about this very thing in class today. Maybe google "test coolant temp sensor".
 
The Yeti

The Yeti

Got 1000 hp?
Re: What would make the ECM go into limp home mode?

TYTILIDIE said:
Personally if it were me I would simply replace the ECM. This was one the very first issues I had with my TY and at the time I knew NOTHING about fuel injection. I took it to a guy here that deals with stuff like this and he replaced the ECM and all was well. It happened again to me about two years ago except it was intermittent. Swapped ECMs and all was well. If I am not mistaken code 55 is faulty ECM. I have yet to ever see this code set on a bad ECM. When your ECM goes bad the "rules" go out the window. If you plug in Datamaster I suspect you will find one of two things, one, everything looks semi normal and still runs like crap or two you will have very strange reading in strange places. Your CTS, in my opinion, will likely flash a code if it goes bad. You can easily tell if it is working when you hook Datamaster up. You can download the software free and use it 20 times. You will need an ALDL cable which you can make for about $20 or buy from $40 to $60 like Dig said. If I were you I would either replace the ECM or buy the cable next instead of tracking this and that down. You're going to waste a lot of time.
Click to expand...

Thanks, I will be making a call tomorrow about the cable and downloaded the software on the webpage already. I am looking for another ECM, I wish I new someone local I could swap one with so that way we could see what mine did in another SY/TY. WHO HAS A SPARE ECM THEY WANT TO SELL!!! :D
 
T

typhoon92

Donating Member
Re: What would make the ECM go into limp home mode?

The Yeti said:
Thanks, I will be making a call tomorrow about the cable and downloaded the software on the webpage already. I am looking for another ECM, I wish I new someone local I could swap one with so that way we could see what mine did in another SY/TY. WHO HAS A SPARE ECM THEY WANT TO SELL!!! :D
Click to expand...
I have one that I'll sell you!
Pm if your intersted
 
SYO237

SYO237

SyTy Registry
Re: What would make the ECM go into limp home mode?

I dont have a spare ECM laying around unfortunately. I need an excuse to goto Melbourne anyhow to go hit up one of my surf shops and maybe surf if there is anything rideable...but I wont be able to get your way for 1-2 weeks. If one of the FAST guys has one they can send me to borrow and take over to Yeti, I'll take responsibility of taking care of it and returning it.

I could probably bring my chip out of the Syclone to try. I also have 50# injectors, but im running code59. Dig...I can safely remove my chip and put it in Yeti's truck without issue right?

Anyhow.... just so we are clear, the truck ran fine before the battery swap? You mentioned you been slowly fixing it since you bought it. What other issues did it have? Possible something in the past is coming back to haunt you?

My assumption from reading all this is either bad ECM (maybe when moving the battery, something shorted and fried the ECM?), or I was going to say bad chip (maybe it didnt burn/emulate right, error'd and phil didnt notice it....it happens, ask me how I know after limping down daytona beach after a bad emulation)....but if the truck ran fine before the battery swap, Im going back to bad ECM. If the ECM swap doesnt fix the issue, my next move would be to get a newly emulated chip to try.

Gary was the only one to mention ignition module/distributor which Ive learned from his experiences are now starting to be common culprits for issues and have become part of the commonly asked "did you check this" list.

Other things to check is fuel pressure, timing, and of course all your grounds again, especially near the battery in the original and new location.
 
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