np man. post up on if you can replicate my setup, and how it turns out

Im having the same trouble as well.

I recently had this problem pop up on me after I had been running the SC set up for about 4 months/3000 miles. I cleared the code, turned the car off for a couple minutes and turned it back on and the problem was resolved. It happened about 3 weeks later and I cleared the code and turned the car off and on to solve the problem. I thought that the problem might have been the Stillen TB wire extensions were being pinched from the steel fuel line inlet into the fuel rail (the Stillen instructions have you bend the fuel inlet line near the pulsation damper and redrill the hole on the mounting bracket. I followed directions and although nothing seemed pinched, it was still tight).

I have the Topgunz SC kit which included the three Stillen extension cables (two long cables for the MAFs and one short one for the TB). Because of the location of the MAF in Topgunz's kit, I only needed to use one of the long cables and the short cable for the TB. I swapped out the short TB cable and have been using the long MAF cable for the TB connectors. Both TB and MAF connectors are identical. It has only been two weeks but no problem yet.

Did you try using the OEM cables instead? Or, similiarly, make sure that every cable was very well insulated? End to end, the entire chain, wrapped up to its *** in sleeves, rubber, plastic, or all of the above

I found that the top maf extension is pinched in between the blower intake and the rad support, pinching the wires on the piping. So I have to take off the whole bumper to fix what may be my problem. Besides that, everything seems fine...
I got the car already SC’ed so I have to backtrack the install to fix a ghost problem.

Michigan Motorsports MAF Mass Air Flow 24 inch Extension
 

Has anyone used these michigan maf extension cables , they are $20 on amazon. Hopefully it will fix the maf and tb extension issue without stillens bs ?

I just ordered one for the tb since im getting the cel and limp mode like everyone.. i'll update after install and let you know if it fixed it .

is it this one?
https://www.amazon.com/Michigan-Moto...omotive&sr=1-1

Yeah that one , is it good ? Has anyone used it yet ?

I have the Gen 2 Stillen MAF cables for $20 with free shipping too.

I just looked looked at the Michigan Motorsports extensions. They are 5-wire extensions. You could not use them to connect to the TB since the TB connections are 6-wire. All of the Stillen extensions are 6-wire so you can use any of the three that come with the kit to extend to the TB.

I will say, however, that I have tried all three of the Stillen extensions to connect to my TB and at some point or another all three have hit me with the P1239 code.

Sorry, that's incorrect. I have one and they are 6 wires and work fine with my Z , not sure if the quality is better then stillen but we'll see how long they hold up. From the amazon pic its hard to see the wires but if u count the holes in the connector u can see 6. I tried to post a pic but it wouldn't upload

I believe its a heat issue with the wires and going to wrap them in a thermal sleeve as some suggested.

I've been having this same issue and it's really affecting my enjoyment of the car. It's happened to me probably 7 or 8 times this summer / fall. Seems to be increasing in frequency. It's to the point where I'm uncomfortable driving the car in heavy traffic b/c I never know when it's going to go limp. I've emailed Stillen about this, but of course, I've not heard back from them. I just ordered the Michigan Motorsports cable, so I'll see if that helps / fixes it. Thanks @Z4fun for finding & posting that!

I would of bought Topgunz cables since he is selling them for $20, if I knew before. Awesome guy, definitely support him !

My issue was the same it ran fine for about 1 year , then started acting up once in a while then more and more often. Cables shouldn't react like that unless there's an external force acting on them to lower the life span like (heat , tention, ice, ect) I feel changing the cable is a bandaid if we don't fix the underlying issue.

I have the car with my mechanic and we are gonna try to find a way to resolve it permanently, if we can reroute them somehow, or if not insulate the hell out of them I will send some pics when we figure it out.

I checked w/ Aaron a while back & the replacement cables that he has are the same ones (Stillen Gen II) that came w/ the full SC kit that I bought from him. So, I'm wanting to try something different. I will also try wrapping / insulating the new cable.

Oh ok , makes sense. Plz post pics of ur fix , im sure all of us would like to see how it came out when ur done.

Hey guys , after some testing and research we concluded the cause is 100% heat. since the wire is being heated its increasing the resistance causing and interruption in the signal throwing the tb off and causing it to go into limp mode.

My mechanic said he tested the wire cold then warmed up the car and tested again and saw a dramatic rise of resistance in the cable. The two options we had is to insulate with a sleeve or try to reroute the wire. Since I am adding a vented hood, we decided to go with the sleeve. (attached pic)


In doing more research this is actually a well known fact in thermal electrical engineering here is the definition for Heat resistance.

Heat Resistance

Heating a metal conductor makes it more difficult for electricity to flow through it.

In metal conductors, electrical current flows due to the exchange of electrons between atoms. As electrons move through a metal conductor, some collide with atoms, other electrons or impurities. These collisions cause resistance and generate heat. Heating the metal conductor causes atoms to vibrate more, which in turn makes it more difficult for the electrons to flow, increasing resistance.

https://nationalmaglab.org/education...eat-resistance


:happydance:

Yes, the actual equation is R=Rref(1+a(T-Tref)) and the temp coef (a) of Cu is +0.000393 per degree centigrade. That means the effect is pretty small at the lengths and temps you would experience under your car's hood. (That Bunsen burner temp in your example link is ~1700 degrees C!)

Example: 100 feet of 20 gauge wire with resistance of 1.015 ohms at 20° C (room temp). If the temperature of the wire goes up 10°C, the resistance will change by 0.0399 ohms (10 degrees * 0.00393 per degree * 1.015 ohms = 0.0399 ohms).

The wire resistance will now be 1.015 ohms + 0.0399 ohms = 1.0549 ohms.

In my opinion, that wouldn't be enough change to account for the large increase in resistance your mechanic is seeing. (I think - I don't know what the increase was. I also don't know how the resistance was measured nor do I know which of the conductors he measured and there are grounds, power, and sensor signals going to the throttle body. You can see that I am shooting from the hip here.) My electrical engineering spider sense is tingling at this point. There could be something else going on - connector pins heating up and losing continuity - something. I hope the proposed solution works - but I am a bit skeptical at this point. Let us know how it goes.

If your engine only goes up 10 degree from ambient that would be awesome, unfortunately for the rest of us with a cable sitting directly on an engine with an oil temp of 115+- C your resistance formula would make a large difference if you wanna recalculate it.

The point of my response was common sense with alittle info in heat and resistance for some ppl that don't need a degree to understand it. That's why I didn't have to pull formulas and stuff. The cause was heat and the failure is the wire or connector under the heat stress over a "PERIOD OF TIME" not a one time thing. materials can heat and cool multiple times before getting to the breaking point.

we appreciate your criticism, but would rather appreciate a solution to the problem at hand.

So I installed the Michigan Motorsports TB cable about a week ago & wrapped it in teva tape, just cause it can't hurt. No codes / limp mode so far, but it's only been a week. Tonight i wrapped it in thermal insulation from Summit. So, we'll see how it goes, although now that it's November in PA, not sure how much more I'll be able to drive the car for a while.

No criticism intended.

It's been a year so how is it now? More reliable?

Yep, so far so good. Although I've only put about 1,600 mi on it. The original stillen cable was OK for a while too, so I'm not sure this is enough of a test to be conclusive. I probably had about 3.5k mi on the Stillen cable before it started crapping out. Fingers crossed.

I also suffered by p1239. Seeing this thread, Hannes was insulated and passed through the summer without any problems. Now that autumn has come, limp mode is back on, and the fault code represents p1239.
It ran about 3,000 mi. Fucxxxx

I'm thinking the only way to fix this problem is to use TopGunz new kit (or piping) that utilizes the stock manifold and therefore stock (length) TB wiring harness. :shakes head:

Would be nice if the extensions were proper length, I had to loop the excess because I didn't know what else to do with it.

Same here.

There is one person who avoided dtc p1239 in Korea. He's been in ride car for five years, and he didn't use the extended harness provided by stillen in the first place.
I twisted the wire of the OEM cable from the starting point to the throttle body. I'll try that and write down the results.

I've had no problems since I switched to the michigan motorsports cable and wrapped it in teva tape and an insulating sleeve. It's been almost a year.

Sent from my Pixel 3 using Tapatalk

Would you have their part numbers ? :tiphat:

I'm curious how frequently this occurs, so far been supercharged for a year with no issues. Should I have an extra laying around?

No not necessarily (Stillen ext cable) because it won't necessarily fix it. You just never know if and WHEN it will bite you. So unpredictable.
I'm interested in the Michigan Motorsports one as an alternative though.

Sure, here you go...
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Thank you! :tiphat:
That's just the MAF extension. Did you get a TB extension from them to?

Thank you bro: icon18 :

I hope for your advice.
How many miles did it run?: 해피 댄스 :

Nope, that's what I'm using as my TB extension.

I have about 3,200 miles on it so far

Thank you! I just bought an extension harness from Michigan -motorsport

lol

OK thanks for that.

After using the Michigan Motors TB harness, hellish p1239 no longer appears. I drove 1000 miles hard.
I've been on the track for 10 times.
There is no problem with harsh track driving.