'97 Cobra/LLX4 problems

twinturbostang · Post by **twinturbostang** » Mon Aug 07, 2006 5:06 pm

I sent Mike G. an e-mail about this, but haven't received a response from him yet, so I figured I'd post it here and see if any of you guys know what's going on...

This is a '97 Cobra with an LLX4 processor. Brand new VT Engines billet stroker, ported "B" heads, and mild clean up work on the intake. Full exhaust, K&N, etc.

First problem I'm having is the TwEECer does not work right. It either does not run at all, or runs like it's running on half the cylinders. With the TwEECer removed or disabled (position #5), it purs like a kitten. I'm using the CDAN4 strategy with bank count set to 2. Just mild changes to the tune so far, like removed EGR and Thermactor (both set to 0), engine displacement set to 302, and fan temp. changes. Doesn't want to run right though. I believe I even read the EEC, wrote that to the TwEECer and tried to run off the TwEECer with the stock tune, but same thing.

Second problem, and this may or may not be related, is the electric fan does NOT turn on! Something strange though... when the EEC is completely removed from the car and the key is then turned to the on position, the fan comes on (engine was hot at that point)! However, when the EEC is plugged back in and the key turned back to on, the fan does not turn on.

Right now, I've "hot wired" the fan to turn on with the key. I shorted pin 46 at the EEC to ground. Basically doing the job the EEC is supposed to be doing. Fan comes on like that, which means the CCRM is working ok. I'm starting to wonder if the EEC has problems though.

Any suggestions???

Brian

Chris Mureen · Post by **Chris Mureen** » Tue Aug 08, 2006 7:53 am

The tune issues sound like they are either:

1. Corrupted binary - get a new one and reload
2. Bad connection on the J3 port
3. Bad Tweecer

As for the fan issue. I am, not certain that your test will tell you if the CCRM is good. But I must agree that it seems like pin 46 should tell you the story. Are you sure the ground wire to the EEC hasn't broken off of the connector? This is a common problem when the EEC is taken in and out a lot. It mounts on the chasis next to the hole the EEC sits in.

Chris

boss96 · Post by **boss96** » Tue Aug 08, 2006 9:30 am

I agree with Chris, sounds like corrupted .bin or the tweecer is not making good contact with the eec connector.
Bob

do'h · Post by **do'h** » Tue Aug 08, 2006 11:22 am

You probably already know this but just a reminder, Uncheck the Update only box before writting to Tweecer this is a gaurantee corrupt tune if left with checkmark.

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 12:21 pm

do'h: I noticed at one point that the update only check box WAS checked, but I turned that off, and I re-flashed the TwEECer several times after that.

I will try reading the EEC again (third time) and writing that to the TwEECer. It definitely could be a connection issue though. I have one of the very first TwEECer's and it has the short connector on it. It was so short that it would not plug in at all. I had to remove it from the case. I have a thin piece of plastic covering the back edge of the EEC, except for a small slot cut out for the connector. This protects the TwEECer from grounding out on anything. Then I place the outer cover back over the TwEECer and tape it all down so nothing moves. BUT, it's possible I'm still not making a good connection with the J3.

Chris: Thanks for the ground suggestion for the fan. I hadn't considered that. I will look tonight to see if it's connected. Although, it seems like it wouldn't even run if it was something like that. The EEC has to have a ground connection for most all functions to operate I would think. But I will check it anyway. I'm almost 100% sure the CCRM is ok because of the way I grounded the fan. I took the wire AT the EEC which is AFTER the CCRM, and grounded that. So current is flowing through the coil in the CCRM and energizing the relay and turning the fan on. Check out this diagram. I drew this diagram a while ago, showing someone how to make a manual toggle switch to turn the fan on, like while in the staging lanes. I've done pretty much what I drew here, except no toggle switch just yet. The wire just goes straight to ground. The coil is fed +12v only with the key in the ON position, so it works good for now... the fan comes on when I start the car, and then shuts off when the engine shuts off.

Chris Mureen · Post by **Chris Mureen** » Tue Aug 08, 2006 12:28 pm

Yep, that looks like it would work and would test the CCRM.

I have seen that little ground wire break and the car did wierd things, but it ran.

Chris

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 12:44 pm

Do you know exactly where it bolts to the chassis? My jumper wire is screwed to one of the dash mounts. Ground wire is probably down farther, closer to the EEC I would think.

Chris Mureen · Post by **Chris Mureen** » Tue Aug 08, 2006 12:47 pm

It is right below the hole the EEC sits in. A little wire comes out of the harness and it bolts to the chassis.

Chris

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 3:41 pm

Thanks, I'll check it tonight. It may actually be possible I removed that when pulling the EEC out and forgot to replace it.

do'h · Post by **do'h** » Tue Aug 08, 2006 4:15 pm

Twinturbostang,

One thing is for certain on my end anytime I read my eec my bins always became corrupted somehow. I battled this for sometime & thought possibly it was hardware problem. I read the eec updated the bin to my specification & saved the file. I kept re-using that saved file "corrupt tune" thinking the bin file was ok but was not. I downloaded a fresh bin off the tweecer website downloads in my case a9l set my strategy to match and it ran great. Just another idea you might want to try.
Good luck.

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 6:07 pm

Yes, I have considered this. No such file on the TwEECer site for LLX4 though. :( I may have found one in the past. But at this point, there's no way for me to tell where the .BIN files on my PC originated, whether from a website, or from me reading my EEC.

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 8:09 pm

Well, the EEC ground wire is there and connected. I'm heading out to re-flash the TwEECer again.

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 8:39 pm

Ok, I tried once again to read the EEC (which worked), and then turn around and flash the exact same thing to each location of the TwEECer (which also worked). However, each time I switch to one of the TwEECer programs, both the fan and the fuel pump come on and stay on constantly. If I switch back to position 5 (TwEECer OFF), the fan and pump turn off. There were two cases however, where switching back to position 5 did NOT turn the fan and pump off. In one case I wrote one of the memory positions and then switched over to 5, and the fan/pump continued to run until I cycled the key. In another case, I switched from position 5 to one of the tunes, and then switched back quickly (within 1 to 2 seconds) to position 5. Same thing... stayed on until I cycled the key.

I'm ASSuming that the TwEECer is connected OK to the J3 port. Otherwise I would think I'd have errors while reading the EEC or writing to the TwEECer.

I don't know what else is going on. Unless the EEC is bad, or for whatever reason the BIN is getting corrupted somehow.

Chris Mureen · Post by **Chris Mureen** » Tue Aug 08, 2006 9:45 pm

Sounds like either the connection isn't good at the J3 or the Tweecer is bad.

86GT · Post by **86GT** » Tue Aug 08, 2006 10:38 pm

I maybe out in left field but don't you have to have a tweecer that supports a 4 bank bin. I thought that it was a different firmware in the tweecer. I also believe that if it is a four bank model then the position 1 and 2 belong to the first store bin and so forth.

Not to sure what happens if you downlod to the position 2 instead of position 1 or 3.

twinturbostang · Post by **twinturbostang** » Tue Aug 08, 2006 11:25 pm

According to Mike G (from an e-mail 2 years ago), 96-97 are 2 bank, and 98 up are 4 bank. I have not tried flashing the TwEECer using 4 banks, just 2. But I have tried flashing all memory positions with the stock BIN that I read from the EEC. Two years ago, I sent it in for a firmware update, and he said mine will "support four 2 bank BIN's, but not two 4 bank BIN's". I never quite understood that, but assumed it was good enough for my LLX4.

As far as the fan problem, that's still up in the air. I don't know what's going on. Everything seems to be connected fine, but the fan just won't turn on the way it's supposed to. Only way it turns on is to plug the TwEECer in, then it stays on all the time. But the engine runs like crap!

86GT · Post by **86GT** » Wed Aug 09, 2006 12:14 am

It looks as if Mike designed the Tweecer to handle two banks for each switch setting. If he indeed did the firmware update then you should be ok.

When you read the EEC into CalEdit did the parameters line up and make sense with the selected strategy? If not then you download the correct calibratin file (bin) but to the wrong memory locations (strategy) to all of the switch settings.

When I download a CBAZA (J4J1) to an A9L(X3Z) the same thing happens. The car may start but it will run like crap and the fuel pump stays on constantly.

twinturbostang · Post by **twinturbostang** » Wed Aug 09, 2006 11:26 am

Yeah, I tried messing with the strategies. Using the CDAN4 seems to be the right one. Engine displacement, injector sizes, fan temps, idle speeds, etc. all look correct. When I change to the CBAZA or other strategies, everything is whacked!

Chris Mureen · Post by **Chris Mureen** » Wed Aug 09, 2006 11:28 am

If you are sure it is making good connection at the port then maybe the Tweecer is bad. I have had it happen.

Is there another car you can try it on to see if it works?

Chris

twinturbostang · Post by **twinturbostang** » Wed Aug 09, 2006 12:49 pm

Yes, it was working fine on a buddy's Procharged '93 coupe (A9L) just a few weeks ago.

Chris Mureen · Post by **Chris Mureen** » Wed Aug 09, 2006 1:29 pm

Seems like it must be the connection then.

twinturbostang · Post by **twinturbostang** » Wed Aug 09, 2006 3:15 pm

But if it was, wouldn't I have problems reading the EEC or reading/writing to the TwEECer? Both of those operations appear to be working properly with no error messages.

Chris Mureen · Post by **Chris Mureen** » Wed Aug 09, 2006 3:23 pm

No, not necessarily. As long as it is getting power it will read and write, but if a couple of key circuit board fingers are not touching then the EEC may not be getting the right data to and from the PCM. Keep in mind that with CalEdit you are only looking at a portion of the file that is moving around. In addition, the Tweecer replaces the entire memory of the EEC, not just the tags modified.

In other words, you may not be seeing the corruption on the screen.

Chris

Dale McPeters · Post by **Dale McPeters** » Thu Aug 10, 2006 1:11 pm

The firmware may need to be updated. I had to send
the one that I bought from Joe Lynch in to have it updated
to the latest and greatest......

twinturbostang · Post by **twinturbostang** » Thu Aug 10, 2006 2:53 pm

I did have it updated. Two years ago I sent it in to Mike and he updated the firmware and did some "jumper fix" I believe.

Dale McPeters · Post by **Dale McPeters** » Fri Aug 11, 2006 11:19 am

twinturbostang wrote:I did have it updated. Two years ago I sent it in to Mike and he updated the firmware and did some "jumper fix" I believe.

Well that is not it........

twinturbostang · Post by **twinturbostang** » Fri Aug 11, 2006 2:19 pm

I've been in coversation with Mike. I sent him an EEC read from last night, and he said it's perfectly fine. It still doesn't work when I enable the TwEECer though.

twinturbostang · Post by **twinturbostang** » Sun Jan 07, 2007 3:48 pm

Bringing this back from the dead...

I'm getting ready to purchase a new EEC. I'm pretty sure it's bad. The following is in regards to my fan issue (not turning on via the EEC). The above tests have verified that the CCRM is working properly, including the wiring between the CCRM and the EEC. Just now I checked all of the grounds on the EEC harness and they appear to be good. So the only remaining thing would be the EEC. I suppose there could be a bad connection between the harness and the EEC, but I kind of doubt it. Since I'm also having problems with the TwEECer working on the EEC, it sounds like I need a new EEC. Off to the parts store I go! :)

Dale McPeters · Post by **Dale McPeters** » Sun Jan 07, 2007 4:44 pm

I am ready to see some of that welding that you have been doing!!!!

codedout · Post by **codedout** » Sun Jan 07, 2007 5:06 pm

If you want to try a cdan4 binary there is one here http://www.moates.net/zips/boothware/ just search for LLX4

'97 Cobra/LLX4 problems

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