Author Topic: ecodiesel questions (Read 3099 times)

nathan.chase · « **on:** November 13, 2007, 11:09:55 am »

I just got a new 92 ecodiesel california jetta A2. I have a few questions and I was hoping there were some poeple on the forum that would know about these cars.

If anyone knows about these cars or knows someone who has one I would love to ask a few questions:

1. the car has an auxilary fan added with a manual switch in th cockpit.
-is this a typical mod and why?

2. There is an aftermarket turbo on it apparently bought over Ebay.
-is higher boost from this turbo not acceptable in the ecodiesel motors?
-is this likely junk? it run fine except an exaust leak at the adapter plates.
3. Hard start? battery seemed alittle weak is there something else potentially? said to have had glowplugs replaced recently
4. what are the timing belt intervals for these cars?
5. there is a bad turbo lag, typical? or exaust leak making that worse?
6. seems when you decelerate or accelerate the car pulls to one side? what is this all about?

thats all for now. seems like a lot of potenial problems but for a diesel with 150k miles on it and a strong 40mpg diesel this seems like a great highway vehicle. I got it for 1500.

thanks for all your help you guys rock!

Turbinepowered · « **Reply #1 on:** November 13, 2007, 11:29:23 am »

The bad turbo lag probably comes from that "aftermarket" turbocharger. ECOdiesels don't compensate fuelling for the boost pressure; the pressure is just there to increase efficiency a little by utilizing exhaust heat, and to clean up emissions a bit. It increases power a little over the stock NA, but not enough to really make note of, and a bigger turbo just spools later rather than bumping up power more, and probably doesn't provide much more boost than the stock turbo.

Stock the ECOdiesels I believe came with the quick-spooling K14 turbo, and I haven't seen anyone complaining about poor spool times with those.

nathan.chase · « **Reply #2 on:** November 13, 2007, 04:54:36 pm »

that great advice. As I understand the full turbo has a fuel pump that boosts the fuel when the boost rises to increase power. this is what you are saying the ECO diesel doesn't have. also I have noticed a real lag with the turbo then in really takes off. this is the spooling delay you are speaking of right? I guess the k15 would be a smoother acceleration and ultimately a similar performing turbo.

Turbinepowered · « **Reply #3 on:** November 13, 2007, 06:02:51 pm »

Quote from: "nathan.chase"

that great advice. As I understand the full turbo has a fuel pump that boosts the fuel when the boost rises to increase power. this is what you are saying the ECO diesel doesn't have. also I have noticed a real lag with the turbo then in really takes off. this is the spooling delay you are speaking of right? I guess the k15 would be a smoother acceleration and ultimately a similar performing turbo.

The fueling compensation is accomplished through a device called an LDA (Don't ask me what it stands for, I don't know, some others here might), which is fitted to the top of a standard pump.

ECOdiesels don't have an LDA, though they true turbodiesel blocks and heads with the oil squirting jets spraying on the pistons and TD exhaust valves.

Yeah, it sounds like your really long turbo lag is from that aftermarket, put a K14 or even a K03 (even smaller turbo) on it and it should spool faster.

Can you see what kind of turbocharger is on it? It should be information on a plate on the compressor housing, which is the not-rusted side of that turbo.

Quantum TD · « **Reply #4 on:** November 13, 2007, 07:08:09 pm »

The ECOdiesel has a somewhat complicated 3-speed fan system. Your car should have 2 fans on it for the radiator. The fans should spin when you turn on the AC or Defrost. They should also kick on LOW when the car sits idling with normal (70-85 degree) ambient temperatures. It should then kick on HIGH at hotter temps or after long trips.

The BAD news is that I don't believe that the Bentley Manual covers troubleshooting for the system. I have an older manual printed in 1992 which lacked a wiring diagram for the ECOdiesel fans system, but Bently may have ignored it since only a handful of the ECODiesels were ever built.

You may need to completely go through the wiring for it. On one that I recently sold, the ground wires for the relays (mounted to the firewall), has melted becasue someone switched the terminals on the back of the smaller relay. The fans only worked with the AC on. I had to completely rewire it and replace the fan switch: took about 5 hours to figure out. Good luck.

As noted by others, the lag is likely due to a larger turbo (bigger isn't always better, unless you have a VNT).

The pulling (torquesteer) is probably due to:
1) Bad struts: this is most likely. If you have a bent strut, it will pull.
2) Bad strut mounts
3) Bad tie-rods or ends
4) Alignment out of whack
5) Bad ball joints
6) bad tires.

All in all, it sounds like you need to go throught the front suspension.

nathan.chase · « **Reply #5 on:** November 13, 2007, 08:47:13 pm »

you guys rock! with the info. I have a mechanic looking at the car tomorrow so I'll have more info tomorrow.

compu_85 · « **Reply #6 on:** November 14, 2007, 01:30:12 pm »

Look forward to it. Always good to see an ECO being taken care of

-J

Quantum TD · « **Reply #7 on:** November 14, 2007, 03:58:04 pm »

Quote from: "libbybapa"

If it pulls to ONE side when accelerating and then pulls to the OTHER side when decelerating then it would be the control arm bushing. On one side or the other. You can figure out which side by which way it pulls, when.

Andrew

Good point. I forgot about those, even though I just replaced some on a MK III TDI just the other day (same as MK II).