VW Vortex - Volkswagen Forum banner
1 - 5 of 5 Posts

75 Posts
Discussion Starter · #1 ·
Hey all,

I have a rough idle and the engine will even die until it's warmed up, then the rough idle continues (not as badly) but the car won't die. I scanned and got the following codes.

P0171 x2
P0174 x2

I will start a visual check in the engine bay but thought I'd post here in case anyone has a better idea of where to look.

Thanks as always!

1,870 Posts
Mine suddenly acted up a few years ago, just like yours: barely idled, ran fine past 2500 rpm. On my car it turned out to be the N90 vvt intake solenoid died. If you have a scanner like Ross-Tech, you can check the values of these measuring blocks:

Valid for both MK4 and MK5 R32:
• Blocks 208 & 209 should be as close as possible to 0°, the spread should not exceed 3°. The absolute wear limit is 8° spread whether + or minus. If the spread is well above 3° but under the limit, then chain & guide replacement should be considered.

Golf 5 R32 & Audi BUB only (intake adjustment range 52°/exhaust adjustment range 42°):
• For both blocks 90 & 91 the set-point value at idle is 0°, no matter what the values in blocks 208 & 209, at a duty ratio of about 15.3%.
The actual value should not be more than 0.5 ° (Valid for both OEM & aftermarket cams).
If the values are way off from 0° the timing chain may be mistimed or skipped. Around 11.25° deviation corresponds to a skip of 1 tooth.

The above can give an indication on the vvts operation. If you can devise a way to apply 12v directly to the valve(s), you can hear them click every time the voltage is applied: on, off for a moment. No click equals a dead vvt solenoid. Simplest way to do this is to get the connectors with their pigtails, either at a salvage yard or elsewhere. I could only find the intake connector. You can just cut the wires if you are comfortable with reattaching them. Like so:

The N90 valves are quite expensive at the dealers, so I wanted to make sure before buying them. You can get them on eBay for significantly less.

1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.