It was the O2 relay on my car too. It would run horribly until it warmed up. Once warmed up, it would run but would occasionally back fire. I did go through the trouble shooting process with Tony's help. That's a good thing to do regardless.

Anyway, I replaced the O2 relay and the problem was solved. It's $12.25 from our host and it takes a minute or two to replace it.

Hhhhhhhh tony you kill me :)
I like the pipe work it's look nice

Engine
 

The answer to both is I dont know:) I am starting with the alternator. It is not charging the battery. You would think if that was the case the light would be on up front which its not. Maybe something else not letting the alternator charge?

Hi Mike,

Thanks for the pics. I will comment on the gizmos on the right hand side tomorrow.

Not feeling too well tonight. Don't even want beer.

Tell us how you know the alternator is not charging. What test(s) did you perform?

Not feeling well enough for beer? Maybe get to ER:). I ran a test with a multimeter to start. I then had a mechanic friend stop by with his tools and do a little trouble shooting. AAA came out with a new battery and confirmed that it wasn't charging the battery. That's as far as i got. I did notice that when I put the key in before I start the car I get no battery/alternator light and after I start the car get no light. Feel better Bob. If you ever get to Dan Diego we will take you out for a few beers:)

Re starting this thread. I had a problem with my SC not charging which members helped me diagnose and fix. Tomorrow will be a cold morning so we will see how things go. This is a cold running problem, not a cold start. During my last fix someone noted that the alternator not charging properly could be part of the problem. I also found out that the plug wires were out of order. That has been fixed. The car sounds much better, now to the cold morning. I have a new O2 relay sensor if needed as some have suggested.

If it is still acting up in the morning, you should perform the earlier suggested fuel system pressure tests so you know at a minimum the baseline and possibly diagnose any problems.

Fuel, spark and compression is what you need, tuning is setting everything where it needs to be. :)

Good luck !!! :)

update
 

Progress but not success. I started the car and had the cold running problem still but better after new alternator. I then replaced the O2 sensor relay. Much better. Still backfiring a bit. Changed the wires and plugs. Firing order was counter clockwise. Much worse. I used NGK Irridium plugs. Are there plugs that these cars hate? A few things I noticed while doing this. At one point one of the fuel lines on top of the engine started leaking gas. Had a bubble and looked old. Fuel pressure high? Sorry for the rookie observation. I also noticed, not related to the cold running problem, an oil leak. It looked to be a leak at the crank pulley which could become another thread once I get threw demon #2. I have included pictures. http://forums.pelicanparts.com/uploa...1386948310.jpg
http://forums.pelicanparts.com/uploa...1386948323.jpg
http://forums.pelicanparts.com/uploa...1386948339.jpg
http://forums.pelicanparts.com/uploa...1386948356.jpg

Descriptive troubleshooting.......
 

Mike,

Could you post the numbers on your WUR? Have you had the chance to measure the fuel pressure readings? Check your engine idle speed with the engine completely warmed up and remove the oil filler cap. Keep notice of the engine speed change (if any). It is hard to tell from your above post if you have improved the running condition or not. Keep us posted.

Tony

Wur
 

I will do that. Thanks Tony! I was going to get the gauges today to test fuel pressure. Where is the WUR located? I am a 944 guy prior and this engine is pretty new to me. Thanks again.

Look for this, over on the left side..

http://forums.pelicanparts.com/uploa...1386951127.jpg

The WUR is located on the left side of the engine, between the intakes for #4 and 5 cylinders.

I have to ask for a clarification of your previous post. You said, " Changed the wires and plugs. Firing order was counter clockwise. Much worse." I interpreted that as you changed the wiring from counter clockwise to clockwise. Is that correct? If so, then you need to change it back as SC's have a counter clockwise firing order.

Intake #2........
 

LJ,

You must be referring to AAR not WUR or simply a typo. The WUR is mounted/bolted on the #2 intake runner located at the left side of the engine where the CDI is mounted. HTH.

Tony

For your reference.......
 

Mike,

Take a look at the picture. Do you know how a WUR looks like? Shown below are cylinders #1-#2-#3 (left bank). The rectangular device mounted on intake runner #2 is the warm-up regulator (WUR). It has a part number of 0-438-140-xxx (right below the hose clamp). Just need the last three (3) digits to identify it.

http://forums.pelicanparts.com/uploa...1386959222.jpg
Tony

Sorry about that. I meant to say kept all in the correct order

Thanks Tony. Yea, it's a typo. Good to have you watching my back:D. Been spending my time working with 4 cylinder VW and 912 engines where the cylinder numbering is #1, 2 on the right and #3,4 on the left. If I don't stop to think about it, the confusion sets in. Anyway, at my age I'm glad I can still count to four.

Numbers
 

The last three numbers are 011.

WUR specification........
 

Mike,

This particular WUR (0-438-140-011) were used in some Audi, Porsche 924, and VW cars in the late 70's and early 80's. You could either insist using this particular WUR which was not intended for your car to make it work or find a suitable replacement. So decision is all yours.

Could you update us of your current CIS problem/s (if any). I'm not sure at this moment what you like to achieve. Keep us posted.

Tony

Update
 

Thanks Tony. I have now tested the alternator, bad, replaced. Fixed the charging problem with a resistor that was not added to the light up front. I went ahead and swapped the o2 sensor relay, plugs and wires. The car at this point is running much better but still has a cold running issue in the mornings with loss of RPM when Idling and backfires. Once warm, after about 15 minutes, it runs fine. However there is a loss of power when your driving and "punch it" to get around someone. the acceleration seems to not respond. My goal is for the car to start and idle reasonably well and to get the power back after warm. Several people have pointed me towards the WUR which I would like to replace with one that is actually meant for the car. I am also going to test fuel pressure today.