Volkswagen Passat Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1
Hello everyone,
I'm a big diesel fan but due to the high cost of diesel and the fact that I was able to take over my wife's 1999 Passat for $850 has redirected me to new interest. I am the facilities Supervisor for a large medical device company in Spencer Indiana (Boston Scientific Corporation) but my back ground is the body business. I painted my first car when I was 13, it was horrible...73 Pinto, but I got better. I have some plans for this Passat...just for the heck of it. This isn't the fist Passat to be in the family its actually the 3rd but the fist I have taken any interest in, I still have no idea why. Out of the 3 this one has been the worst. Power sucks and it has had more issues that any of the others. Go figure..it would be the one I ended up with. I have been reading threads and making repairs for 2 weeks. I am however stumped on two things, I am only going to address one at this time. I have read every thread and searched all over the net and I think I'm close but still no prize. Its time for you all to cringe when I say....SAIR! But wait! I think I have something new because I haven't found it anywhere and believe me I have been looking....HARD! Okay I should probably post this somewhere else but I'm new so scold me if necessary. Here goes. Okay when I apply 12V to the pump it runs...check the fuse...Okay its fine....replace the relay...four relays later no change. I took the cover off of one of the relays and I can manually engage the relay and the pump will run. This this is making me crazy! If it want for that damn "check engine" light blaring at me I would delete the dang thing but I hate the check engine light...a lot! If anyone has any ideas please let me know and then we will work on the next issue.
Thanks all!
 

·
Moderate Moderator
Joined
·
16,485 Posts
First off... Is the SAIP spinning up on its own when you cold start the car?
It should run for 50~100 seconds at cold start.
You may need to get your head down near the passenger front corner of the car to hear it.

What code numbers is it generating? I'm guessing you have the V6?
 

·
Registered
Joined
·
12 Posts
Discussion Starter #4
No it will only spin up if I take the cover off the relay and force it with my finger or run 12v directly to the pump, I can hear it spool up just fine then. It was working just fine about 3 weeks ago, it was always very audible, the it just quit. I have the 1.8. I haven't had the code read yet. I am going to stop by Autozone tomorrow on my way home from work and have them ran.
 

·
Moderate Moderator
Joined
·
16,485 Posts
Is it the ATW engine then?

You've proven the circuit that relay controls is functioning. Sounds like the relay isn't getting triggering voltage or ground. Bentley says the pump should run at cold start (41ºF to 91ºF) coolant temperature. It also says after each subsequent start (up to max. 205ºF engine temp), the SAIP will cycle in for 10 seconds during idle and will be checked by the OBD.
 

·
Moderate Moderator
Joined
·
16,485 Posts
The relay trigger voltage comes directly from the ECM (.35mm blue/gray wire) (pin 66 of the T121 pin connector). Check continuity between that pin and pin 6 of the relay socket.

Ground for the coil of that relay (.50mm green/yellow wire) goes to the engine wiring harness ground wire. That harness ground wire is also the ground for the evap purge valve, N75 valve, SAIP vacuum solenoid valve, MAF... and a bunch of other things that appear to be working. Check continuity between pin 4 of the relay socket and frame ground.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #7
Its a 1.8 BTW. Not sure what ATW is but I'm sure you do. I will study this tonight when I get home. I agree that the trigger isn't there for some reason, so far I haven't read anywhere about anyone else having this issue. I'm sure its related to another issue. I will try to get some codes tonight after work and post.
Thanks
 

·
Moderate Moderator
Joined
·
16,485 Posts
They used the AEB engine code 1.8t from 1998 to some time in 1999? Then they changed to the ATW engine code 1.8t. They are pretty much the same engine with some design changes. The three letter code is stamped into a tab up at the front end of the head. My 1999 has an AEB and no SAIP system. I wanted be be sure I was looking up the correct wiring diagram for your engine.

Some folks say VW really stands for Varies Widely. :)

Not having a SAIP myself, I don't know if the system stops cycling in when the temperature drops too low (see post #5). I imagine Indiana is seeing sub 40ºF temps right now.
Post up the trouble code numbers when you get a chance.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #9
Hey Steve
Yep you got that right its 23 right now, probably a heat wave to you. I have spent a lot of time in Chicago over the last 3 years having my leg reconstructed at Rush University. Great city! Long drive! Anyway I have a P1433 code which is pointing to a bad relay so it is possible that the relays I am trying are not compatible with the car. 2 brand new ones and 2 used ones. You lost me a bit on the pin checking. Are these pins in the ECM box under the hood with the relay?
 

·
Moderate Moderator
Joined
·
16,485 Posts
P1433 - Secondary Air Pump Relay (J299): Open Circuit

Possible Symptoms
* Malfunction Indicator Light (MIL) ON

Possible Causes
* Fuse(s) faulty
* Wiring and/or Connector(s) from/to Secondary Air Pump Relay (J299) faulty
* Secondary Air Pump Relay (J299) faulty

Possible Solutions
* Check Fuse(s)
* Check Wiring and/or Connector(s) from/to Secondary Air Pump Relay (J299)
* Check/Replace Secondary Air Pump Relay (J299)

Yes, the relays may be faulty, but you've tried 4 of them? Are they new, used, generic, trusted?

Yes, the pins are in the ECM box. Pin 66 of the 121 pin connector on the ECM has a blue with gray stripe wire that goes to pin 6 of the relay socket. This is trigger voltage from the ECM to the relay. This current goes from the ECM, through the relay coil and causes a set of contacts to close. Current then comes out of the relay coil to pin 4 of the socket. Pin 4 is connected to a ground wire common to several things in the engine bay. That's the entire "control" side of the relay circuit. The other (being controlled) side of the relay is the high amp power being switched on/off to power the pump. You've proven that side/circuit works as it should when you manually closed the contacts and the pump spun up.

Check continuity between ECM pin 66 (of the 121 pin connector) and pin 6 of the relay socket.
Check continuity between relay socket pin 4 and frame ground.
Both those conductors should show good continuity.

Check all the fuses. I don't know which fuse is used to power the circuit providing relay trigger voltage from the ECM.
Test fuses with a meter or test light. Sometimes bad fuses will still "look" good.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #11
Will do! Ill try to get started on this tomorrow. I hope it warms up a little or its going to be later in the week. Thanks again for your help. I will follow up when I find something out.
2 Generic relays and 2 used
 

·
Moderate Moderator
Joined
·
16,485 Posts
Even if they function, it doesn't mean they present the ECM with the load it's looking for.
I don't know what the resistance spec is for the coil.
A short or open he'll be able to detect.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #16 (Edited)
Here is some news that might change a few things. The title says its a 2000 not a 99. I was looking at the door tag, it says 10/1999. So what I have found so far is that the relay is good. The pin closest to the fire wall has power. I didn't go any further because I didn't figure the color codes on the wires would apply due to the new information about the year of the car. I checked the 40 amp fuse it test good and I ohm-ed out all the other fuses by the drivers door all tested good. Is there any other fuses to check? What are the relays behind the dash? Do any apply?
Another thought. I have 2 other codes P1137: Fuel system too rich and P0102: Air flow sensor circuit low input. Could either of these be telling the ECM to shut of the SAIR?
Thx!
 

·
Moderate Moderator
Joined
·
16,485 Posts
The 2000 model year explains why it's an ATW engine. Wire colors and pin positions are the same as listed above. I don't know which pin is closest to the firewall. If it's pin 8, it should always be live, even with the key out. That's the power coming from the 40A fuse. That's also the power that gets directed to pin 2 when the relay closes (then on to power the SAIP). You proved that part of the circuit is good back when you closed the relay contacts by hand. The power in question is the trigger voltage (what causes the relay to close) coming from the ECM. Also the ground for that side of the circuit (pin 4 to frame ground).

I don't know about the other codes causing the SAIP not to run.

Are you clearing the codes after each round of testing/fixing? If the ECM tried to run the SAIP while you had the relay out (or a bad relay installed), it'd log the P1433 code. If the relay was bad and you replaced it with a good one, the P1433 code would stay in memory till you cleared it.

As for the other two codes, it's likely they are related. The air flow sensor is what the ECM uses to measure the intake air so it can calculate how much fuel to deliver. Those two codes are telling you something is wrong with the intake air measurement and fueling is not correct.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #19
Hi Steve
Problem solved. Ended up being a mass air flow issue. All lights are out and everything is working great. Thanks for your help.
 
1 - 20 of 21 Posts
Top