Jumped on the "Crazy Train"

[4.2Crew]

Still the following codes:

17416 P1008 MAF 1/2 sensor implausible

17536 P1128 Bank 1 too lean

17538 P1130 Bank 2 too lean

You may want to ensure the SAI (Secondary Air Injection) system is "tight".... Check all vacuum lines to ensure they aren't cracked and hold a vacuum. Also, there is a large plastic/rubber hose at the back of the engine that connects vacuum actuated air valves on each bank (they are hard to see/reach)... That hose can degrade over time (very close to exhaust heat) due to heat cycling etc... Can result in these codes.

[905084]

Definitely going to check the SAI system when I do the Apikol seals this week.

As far as the aux radiator delete the only reason I didn't do it was to keep the marketability of the car. Might want to check with a radiator shop to see if it is an easy fix.

[kday]

The radiator leak appears to be at the seam of the plastic tank and the core. I think there's usually a gasket in there. I doubt it would be economical to repair.

On the intercooler fix -- what did you use to remove the fins between the bars, near the endtanks?

[905084]

I used an old woodworking chisel. It is 1/4 inch wide and fits perfectly between the bars of the core. It has a sharp edge that cuts the heat sink material easily, but not the bars or the end plate as they are much thicker.

To start, drill out the heat sink material at the corner using one size smaller than 1/4 inch (my first one I used a 1/4 inch bit and rounded it a bit and cut the bar material as it is fairly fragile). Then use the tool to scrape away all the heat sink material. It looked like this before the JB weld.



Here is a pic of the tool. I'd recommend buying something similar if you can find it.



I sanded the spots I could get, then cleaned it with a Q-tip in acetone. For the application of the JB weld I would recommend thinning with acetone (I think it was 1tsp per 2 oz.) then applying with a syringe to get it to flow between the bars. Walgreens had the perfect size with a little cleaning brush with it that worked great.

[4everRS]

905084, Great tips. Love to see the picts too!

To verify, was the leak coming from where the bars came to the end tanks?

[905084]

Yes, the radiator shop I took the first I/C to put it in the water tank and 3 of the 4 corners where the bars go into the end tank were leaking. The bars aren't welded to the end tank. I guess they use heat and hope to get it to seal.

I also ran a bead of JB down each side of the end tanks just as an added measure to help seal and support the I/C.

[kday]

Thanks. Will give it a try tonight. So you didn't have any leaks except for the corners?

Last night I cleaned the intercoolers with dish soap. Lots of crud came off. I did this in the bathtub since there's no slop sink in the house. I would JB weld them on the dining room table except it's already covered with my wife's paintings so I can't!

[905084]

No other leaks that I know of. I went down the sides of the end tanks with the JB "just in case". I pressurized it to about 15 psi and let it set for 5 minutes and the pressure stayed the same. Any leak smaller I assume is inconsequential due the the CFM that the turbo puts out.

I think all of the gunk on the I/C is oil from the turbo and not road grime. I took mine to the local car wash and pressure washed them before I started to really clean the area around the tanks. If you do that, just don't hold the sprayer at an angle too close to the heat sink fins or they will bend.

[905084]

Apikols!!!! Old seals out with tennis balls inside shopping bags to prevent FOD from going down the intake. Cleaned the intake with Q-tips and acetone.



Apikol seals installed.


Test drive time....still has cold running issues with the SAI pump running, but this is the first time I felt like I had a beast! WOW!! I had to go to Hope Depot and after driving there, I walked in with the biggest grin and tears in my eyes 'cause I FELT IT!! All the work has been worth it and I'll keep working because I know how great this car can be! Still throwing the same MAF codes but it's all good!

[kday]

Awesome!

Mine felt pretty beastly already but I'm hoping for more once I get my IC leaks fixed.

[905084]

Same MAF codes, Signal implausible, Bank 1/2 too lean. Took the airbox off and found my left Apikol seal half in the turbo inlet! Got to say, the whole carbon fiber airbox installation is a goat rope on this car with the left MAF wiring harness in the way.

Managed to salvage the seal, took both the MAF's off the airbox and put them in the intake with the seals then put the airbox on. Left the MAF's unscrewed to the airbox. About 10 times easier with no codes.

[905084]

More troubleshooting. Bought a 99 cent cable on eBay, downloaded the VCDS lite software and spent 4 hours trying to get it to work on my 'puter. Finally got the car to talk to the computer and started it up. G70 MAF reading essentially zero while G246 reading "normal" or about 5 at idle. Swapped MAF's and then had G246 reading zero. Bad MAF. Had a cheapie MAF for an Audi TT that I took the sensor out of and put in the RS housing. Started it again and G246 reading a little less than G70 but working. Went for a spirited drive and had a blast! Made my wife giggle....

Not sure why the ECU doesn't flag the bad MAF in its software, but you have to have at least VCDS lite to troubleshoot this problem.

Probably order a new MAF tomorrow but at least the beast is a beast and driveable. Except for the occasional transmission slipping out of gear on acceleration............

[Chung]

I get a check engine every now and then for MAF but it is not consistant.

I am thinking about using your approach to the airbox. Do you notice any leaks around where the MAFs connect to the airbox? I wouldn't want air from there because it is past the filters.

I think speedtrapped used a little bit of superglue to hold the Apikol seals in. Mine just arrived so I need to decide what to do there.

[905084]

Apikol sent me some glue with the MAF but it did not work particularly well. If I were to do it again I would use a band of RTV to put the Apikols in, push in the MAF then let dry. Then pull out the MAF and attach to the airbox (heck, I will probably go back and do it this way). Because the seals are tight, it is difficult to center the airbox (with the left MAF plugged in) and ensure they are centered before you push down the airbox. If it is not perfectly centered and you try to push it in and there is no glue or it is not dry,, you can wind up pushing half the seal down the intake like I did.

As for the intermittent MAF, I was troubleshooting mine and cut the insulation cover off the left MAF. Yikes!, bare green signal wire in 2 places... pulled on it and it came apart in my hand. Added some wire and soldered and now functioning, but needs a complete rewire. I only mention this because this signal wire is shielded to ground and the bare signal wire was cut about where the shield ends. Now if your signal wire were to short to ground, I imagine you would have an intermittent MAF reading.

The MAF wires and the MAF's themselves live in a very hot environment right above the turbos which probably accounts for the high failure rate.

[Chung]

Same MAF issue with as mine. Bare wires that read every now and then. I am going to do a rewire on mine which will hopefully solve my issues.

[NSU RS6]

Apikol sent me some glue with the MAF but it did not work particularly well. If I were to do it again I would use a band of RTV to put the Apikols in, push in the MAF then let dry. Then pull out the MAF and attach to the airbox (heck, I will probably go back and do it this way). Because the seals are tight, it is difficult to center the airbox (with the left MAF plugged in) and ensure they are centered before you push down the airbox. If it is not perfectly centered and you try to push it in and there is no glue or it is not dry,, you can wind up pushing half the seal down the intake like I did.

As for the intermittent MAF, I was troubleshooting mine and cut the insulation cover off the left MAF. Yikes!, bare green signal wire in 2 places... pulled on it and it came apart in my hand. Added some wire and soldered and now functioning, but needs a complete rewire. I only mention this because this signal wire is shielded to ground and the bare signal wire was cut about where the shield ends. Now if your signal wire were to short to ground, I imagine you would have an intermittent MAF reading.

The MAF wires and the MAF's themselves live in a very hot environment right above the turbos which probably accounts for the high failure rate.

Careful with Silicones, I have heard they can screw up OX sensors. Use this:

http://www.permatex.com/products/aut..._Sealant_a.htm