[JettaRed]

I just installed the progressive (Universal Stage 2) kit and everything seemed to have been working fine for about a day. This afternoon, though, the car started idling rough. And, I've noticed that the pump will randomly turn on while I'm driving under vacuum (no boost)--both the green and yellow LEDs flash on and off.

I check my stored DTCs and I get a couple of errors:

17511 - Oxygen (Lambda) Sensor Heating; B1 S1: Performance too Low
P1103 - 35-00 - -
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16685 - Cylinder 1: Misfire Detected
P0301 - 35-00 - -
16687 - Cylinder 3: Misfire Detected
P0303 - 35-00 - -
16688 - Cylinder 4: Misfire Detected
P0304 - 35-00 - -

I changed out my plugs and moved around the coil packs. I cleared the codes, did throttle body adaptations, and even disconnected the battery for a while.

Finally, I disconnected the water to the nozzle and that seems to improve the situation. Also, with the line disconnected from the check valve, water would randomly pulse out.

Now, while driving, that isn't much of a problem. However, while idling, the engine wants to stall.

More than the misfires, I'm concerned about the O2 sensor DTC. It's the pre-cat one. I've used water injection before (Aquamist) and didn't have these problems. I'm sure it's a matter of just getting things right.

BTW, I'm using the 3 gph nozzle on a 2004 Audi TT with peak boost around 22 psi. I have a single nozzle set up mounted to a throttle body flange adapter.

What changes should I make?

[Rocket468]

Sounds like the green wire of our controller does not have a good connection with the map sensor. On your car it should be the purple with the gray stripe. It should not be turning on and off.

[JettaRed]

I will double check. It is connected to the purple/gray wire, but it's VERY thin. How about the nozzle? Because of location, should I go smaller? Any ideas about the O2 sensor? Also, the misfires occur while driving, as well.

[dvldoc]

Your getting the missfire because the system is kicking on while the car is not under boost.

The very thin wires can cause a issue when it comes to a good map signal you either need to strip it down more and ensure more contact is made and then solder it.

When the controller looses the signal it will hunt and this will cause the pump to turn on and off. You can disconnect the blue wire from the pump until you have the map wire connection solid. Then do a test drive, It should not activate until you hit your set points.

[JettaRed]

Thanks. I have disabled the system entirely for now. I had the crap scared out of me this morning at 5:00 when I left for work. I had filled the washer tank yesterday, but the low fluid light came on this morning. There was no fluid on the drive and I could only guess that over night it had pumped 3 quarts into the intake. I suspected that the fluid drained back into the intake piping and not the engine because I had started the car before the light came on. So I spent the next hour and a half disconnecting the lower pipes and checking everything out--no fluid anywhere.

The only thing I can figured that happened is that the 3 gph coming on at 7 psi and maxing at 15 psi was tooooo much--apparent by the misfires. Coincidentially, the fluid was at the borderline low level and the light came on. I drove about 35 miles this morning with the system disconnected and had no idling problems or O2 DTCs. So, this afternoon, I will connect things back up, but set the initial threshold at 12 psi and max at 22 psi.

Should I go with a smaller nozzle? The calculator says I need about 3.x gph at 100 psi. With the pumps operating at 150 psi, should I go smaller, like 2 gph?

thanks

[dvldoc]

Just make sure you check your settings, and your connections, 7psi is probably to low for you. You can also raise the full point and this will spray less at the lower psi of boost. But If the vehicle is not Knock prone at that psi you should not set it that low if your getting misfires.

[JettaRed]

OK, here's what I think was happening. After having a discussion with Chance, he said my idling problems sounded like a vacuum leak. So, I checked all the connections and still had the problem. I then started to examing the check valve--it looked like some debris was caught against the rubber ball. I removed the check valve and blew some compressed air through it in the direction of water flow. Then, to make sure, I disassembled the check valve and found it to be a simple spring and ball valve. I reassembled everything and reinstalled the valve. No more idling problems.

I also added over a quart of fluid to my washer tank after driving only about 35 miles. I'm now believing that the check valve was leaking all the time and consuming fluid continously when under vacuum (which is probably 95% of the time). When driving, I didn't notice the leaking water, but at idle I did.

For extra credit, I soldered the green wire to the MAP signal wire instead of using the quick connector. I was told that will probably eliminate the random short bursts of the pump.

Haven't taken it for a test drive, but will report back when I do. I did order a 2 gph nozzle because of the proximity to the intake. I'm more concerned with knock suppression than cooling the charge.

Keeping my fingers crossed!

[JettaRed]

BTW, I did get a code on the drive home; P0135 which is an O2 error. If I was continously drawing water into the intake when under vacuum, that may be the reason why.

[dvldoc]

Not normally unless it was excessive, See if the code clears after you reset it if you have a scan tool or disconnecting the battery.

Debri in any check vavle can cause a leak, Sounds like you covered all the problem spots and should be set. When it comes to the MAP wires that are 22g and 24g you should not use the quick connects on them. They are just two small to get a good solid connection. Some of the older GM cars the wire is around 26gauge and can be severed by quick connects.

You should be good to go now.

[JettaRed]

I'm convinced now that the primary cause (maybe the only cause) of my problems was the debris in the check valve. Cars running great now. Now, I'll start the tuning again.