UhOh
Top Post Dawg
Verified the rumor that the daughter's wagon (auto) runs rough when first started. The engine fires off nearly instantly. Then it stumbles and runs pretty rough. I have not had enough time to see at what point it smooths out: all reports is that it does as it starts to warm up.
This car is kind of an outcast in that I don't have ready access to it. It is now in my possession for a full suspension refresh and some other things (not related to engine).
Here is some history/observations (all work has been performed by me):
- No codes (Ultragauge recently installed and I saw nothing coming up on it);
- Replaced TB;
- Compression test showed very good cylinder-to-cylinder balance (well within spec), readings with cheapo tester were all above 500 psi;
- Replaced MAF (previous one was a bit weak per VCDS);
- Timing set max advance (following TB job);
- Swapped out auto injectors w/manuals (from wife's car-known good & with commensurately same mileage);
- Injector deviation good (need to double-check, but I believe it was good);
- IQ around 1.8 - 2.4? (I lost my notes; I seem to recall it being low; was waiting until after the tune to adjust);
- CTS replaced (son did this job);
- Malone Stage 1 tune (just done within last two weeks- problem proceeded this, was hoping that the tune might magically fix)
Nearly all threads/discussion related to rough running when cold all seem accompanied by difficulty in starting. This car, as noted earlier here, starts instantly: I don't know if I've ever experienced a car that starts more quickly. Because of this I figured that this situation was worthy of creating a new thread.
I'll be posting observations and what changes I undertake. Right now it's not a high priority (suspension work will be). Figured I'd give a little time here for things to brew; maybe someone has had this exact situation. Off the top of my head I plan on doing:
1. Unplug MAF (this is stumbling just like my wife's car did when that car's MAF totally crapped out- it was running pretty much fine and then its MAF just completely crapped out- was stumbling/shuddering and just as soon as I unplugged the MAF it smoothed right out- NO CODES!);
2. Verify timing is still holding (fact that it runs so darn well would tend to say so, but need to see actual numbers);
3. Do a full scan with VCDS (again, not seeing anything being reported);
4. Unplug CTS;
5, Verify fueling (check thermo-T [fuel filter change recently]).
There's no clear fuel line on this thing, which kind of leaves me in the dark on the fuel side of things. Not sure if no clear lines is common with auto-trans cars or not.
This car is kind of an outcast in that I don't have ready access to it. It is now in my possession for a full suspension refresh and some other things (not related to engine).
Here is some history/observations (all work has been performed by me):
- No codes (Ultragauge recently installed and I saw nothing coming up on it);
- Replaced TB;
- Compression test showed very good cylinder-to-cylinder balance (well within spec), readings with cheapo tester were all above 500 psi;
- Replaced MAF (previous one was a bit weak per VCDS);
- Timing set max advance (following TB job);
- Swapped out auto injectors w/manuals (from wife's car-known good & with commensurately same mileage);
- Injector deviation good (need to double-check, but I believe it was good);
- IQ around 1.8 - 2.4? (I lost my notes; I seem to recall it being low; was waiting until after the tune to adjust);
- CTS replaced (son did this job);
- Malone Stage 1 tune (just done within last two weeks- problem proceeded this, was hoping that the tune might magically fix)
Nearly all threads/discussion related to rough running when cold all seem accompanied by difficulty in starting. This car, as noted earlier here, starts instantly: I don't know if I've ever experienced a car that starts more quickly. Because of this I figured that this situation was worthy of creating a new thread.
I'll be posting observations and what changes I undertake. Right now it's not a high priority (suspension work will be). Figured I'd give a little time here for things to brew; maybe someone has had this exact situation. Off the top of my head I plan on doing:
1. Unplug MAF (this is stumbling just like my wife's car did when that car's MAF totally crapped out- it was running pretty much fine and then its MAF just completely crapped out- was stumbling/shuddering and just as soon as I unplugged the MAF it smoothed right out- NO CODES!);
2. Verify timing is still holding (fact that it runs so darn well would tend to say so, but need to see actual numbers);
3. Do a full scan with VCDS (again, not seeing anything being reported);
4. Unplug CTS;
5, Verify fueling (check thermo-T [fuel filter change recently]).
There's no clear fuel line on this thing, which kind of leaves me in the dark on the fuel side of things. Not sure if no clear lines is common with auto-trans cars or not.