Engine identification ?

[Strikefalcon]

what is the best way to identify a 98 Jetta engine? Or maybe a better question is will a mostly complete, was running when pulled engine be a mostly bolt in swap? and no difference if a Z1 or AHU?

 

[IndigoBlueWagon]

The differences between a 1Z and AHU are mostly internal and also minor. One way to tell is most AHUs have an EGR cooler, and 1Zs typically do not. So if the intake assembly is on the car look for a cooler to see if it's an AHU.

 

[Steve Addy]

Look at the upper timing cover, if the decal is still present it will say AHU or 1Z on it. My 97 Jetta tdi has a 1Z with EGR cooler.

If it's a 98 the probability is pretty high that it's AHU. The general rule of thumb has been that 97 Passat and 98+ Jetta TDI both got the AHU.

The trunk decal is never correct on the Mk3 cars.

 

[ToddA1]

I was under the assumption Passats were always 1Z. The donor 97 Passat for the project car, turned out to be a 1Z.

My 97 Passat has the egr cooler and I assumed it was a 1Z....

-Todd

 

[IndigoBlueWagon]

The trunk decal is never correct on the Mk3 cars.

So true. We were at a GTG years ago and there were three MKIII cars there: none of the trunk stickers were correct.

I, too, think that '97 Passats had AHUs in them.

 

[ToddA1]

Well, I’m aware of one 97 B4 that didn’t. If I have time, I’ll take a look at the other 97 B4, tomorrow.

I’m curious about the trunk decal, now... I’m positive my 96 B4V decal is correct.

-Todd

 

[IndigoBlueWagon]

How would you confirm whether your '97 is an AHU or a 1Z? I wouldn't mind knowing what mine is: I've always assumed it was an AHU because of the EGR cooler. I know there was the whole thing about the 1Z having a red dipstick tube (or was it yellow?) but so much time has gone by now it's unlikely any car still has the original tube.

 

[ToddA1]

The stamping on the block. Should be between #3 & 4 , at the flat part, above the breather. VW has been doing this for decades... I thought this was common knowledge. It’s sometimes hidden by grease, rust, etc.

-Todd

 

[ToddA1]

Originally, the dipstick tubes were red, but I agree that’s a poor indicator, although red ones are nla.

-Todd

 

[ToddA1]

I checked the 97 B4, but it’s too hard to see. Have it quick steel brushing, but no dice. I wasn’t taking the car apart, to see what it was. i opened the trunk and forgot it was being used as temporary gti parts storage... wasn’t going to empty the trunk to look at a decal.

I did take a pic of the stamping from the 97 B4 donor engine.




The stamping is very shallow... no wonder it can’t be seen on cars that get standard use. If the block wasn’t cleaned and painted, it’d probably be overlooked.

-Todd

 

[Steve Addy]

Well, I’m aware of one 97 B4 that didn’t. If I have time, I’ll take a look at the other 97 B4, tomorrow.

I’m curious about the trunk decal, now... I’m positive my 96 B4V decal is correct.

-Todd

Todd
I believe the B4 trunk decals are correct, I've never seen one that wasn't. The Mk3 OTOH are always wrong and every one I've ever seen say 1Z (for engine) and AMC (for trans) no matter what's under the hood, that includes my rotten green 98 Jetta donor with AHU. I might also have seen one that says trans is CHA too, but that I don't remember that clearly.

I'll check my 97 B4 next time I'm down at the shop. I don't remember if it has a trunk decal or not TBH, I didn't get a key for the trunk when I bought it. What I do know is that it's a post-5th injector car with EGR cooler with the later ECU, I did check that when I bought it.

Steve

 

[Steve Addy]

Originally, the dipstick tubes were red, but I agree that’s a poor indicator, although red ones are nla.

-Todd

Originally the dipstick handle itself was red too...but those are NLA too unfortunately..

Steve

 

[turbodieseldyke]

I believe the B4 trunk decals are correct, I've never seen one that wasn't. The Mk3 OTOH are always wrong

Accuracy is oddly correlated to the VIN first digit

 

[IndigoBlueWagon]

First number? Mine's an 8.

 

[turbodieseldyke]

Wolfsburg is likely a much tighter ship than... Wherever the "3" cars are built. Certainly more so in 1997.

 

[IndigoBlueWagon]

I thought a lot of B4s were assembled in Belgium. But I suspect the vins all start in W. 3 cars are Mexico.

 

[Steve Addy]

I thought a lot of B4s were assembled in Belgium. But I suspect the vins all start in W. 3 cars are Mexico.

Yes, B4's were assembled in Brussels but VIN still read WVW. I think majority of B3 cars were assembled in Emden Germany. All Mk3 save for the 1994 Jetta GLX VR6 and some Cabrios were assembled in Puebla Mexico. Eventually even the GLX and Cabrio all came from Puebla.

EDIT: just went out and checked the B3V to ID the engine. The donor was a 1998 Jetta and the engine says AHU on the block.

Steve

 

[ToddA1]

The 98 Jetta engine being an AHU doesn’t surprise me. I’m curious what your 97 B4 is.... I’d bet 1Z.

-Todd

 

[Steve Addy]

The 98 Jetta engine being an AHU doesn’t surprise me. I’m curious what your 97 B4 is.... I’d bet 1Z.

-Todd

I'll check next time I'm down there, both the 97 B4 and the 97 Mk3.

Steve

 

[IndigoBlueWagon]

Pulled up the carpet in the trunk and removed the spare today. No sticker.

 

[ToddA1]

Well, I had a flat tire and I was forced to empty the trunk.

97 B4 with an egr cooler.




1Z, as expected. As mentioned, I don’t think the Passats got the AHU. 1Z or AHU is a Jetta thing.

My new dilemma is I need to buy 2 cheap tires and install them on my terrible looking wheels or install the coilovers and heavy wheels which will make my dismal mileage even more dismal....

I think I’ll go for option 1... I’m lazy.

-Todd

 

[Abacus]

Oh man, I have two 14" Nokian snows I'm getting rid of cheap since both B4's use 15" now.

 

[ToddA1]

Thanks for the offer, but I remembered I have brand new snow tires mounted on Rondos. I may install these or the snow tires from the Rotbox. Decisions, decisions...

-Todd

 

[Steve Addy]

Well, I had a flat tire and I was forced to empty the trunk.

97 B4 with an egr cooler.




1Z, as expected. As mentioned, I don’t think the Passats got the AHU. 1Z or AHU is a Jetta thing.

My new dilemma is I need to buy 2 cheap tires and install them on my terrible looking wheels or install the coilovers and heavy wheels which will make my dismal mileage even more dismal....

I think I’ll go for option 1... I’m lazy.

-Todd

I expected that your decal would be accurate, the B4's don't seem to have the same issue with accuracy that the Mk3's did. Then again they didn't come from Mexico either.

I looked at my 97 Jetta and the engine code is 1Z, which I expected. It's barely visible though. On the 97 B4 the engine code is also 1Z but it was much easier to see! The build date on the B4 was 12/96 so I'm not sure when they actually stopped production of the B4's but it's probably a mid-year car. IIRC August is the new MY start for VW. I know that Mk3's were produced up to 12/98 (1999 cars) and then halted, but that was because Mk4 cars were late getting here for some reason.

Steve

 

[ToddA1]

My only point was the 97 B4 would likely not have been AHU, even if it had an egr cooler, as previously mentioned. I’m no expert, but every tdi B4 I’ve ever seen was 1Z.

-Todd

 

[oilhammer]

Every A3 TDI I've ever known was an AHU. Every B4 TDI I have ever known was a 1Z. Even my '98 Jetta's trunk sticker said 1Z with the AHU clearly stamped in the block. This was around the time VAG was changing engine code IDs from two to three digits.

 

[Steve Addy]

Every A3 TDI I've ever known was an AHU. Every B4 TDI I have ever known was a 1Z. Even my '98 Jetta's trunk sticker said 1Z with the AHU clearly stamped in the block. This was around the time VAG was changing engine code IDs from two to three digits.

Every mk3 tdi car I've ever seen had this same engine trans combo on the decal. The only time it was true was for 97's and then only for the engine and not the trans. The B4, not coming from Mexico, never had this problem.

Steve

 

[oilhammer]

I am not sure what Mexico has to do with anything. That tag looks the same as my '98 did. What is interesting is that all the tech info only shows AHU or AAZ for the A3 Jettas.

Most of the B4s were assembled in Brussels, Belgium. While the 'W' in the first place seems to have originally been to signify West Germany, it later sort of became "Greater Europe" instead. Because even the Slovakia- assembled cars (T'reg, Q7, etc.), Austrian-assembled cars, Portugal-assembled cars (Eos), and all the Belgian-assembled and I think even some Polish-assembled cars all carry the 'W' in the first digit. VAG breaks down which plant in the VIN, though, I forget which digit. But Turkey is different (first gen TT came from there, as do many little Ford Transit Connects, Promaster City (Fiats)). Great Britain is different. Not sure about Spain or Italy, but they may have their own code...Italy probably does anyway.

 

[Steve Addy]

I am not sure what Mexico has to do with anything. That tag looks the same as my '98 did. What is interesting is that all the tech info only shows AHU or AAZ for the A3 Jettas.

Mexico was a problem with Mk3 production from the beginning. As I'm sure you're aware, production delays in Mexico caused big problems when the Mk3's came out and then in addition to that the quality issues with Mexican production caused stoppages that took time to resolve. There may have been a strike as well, I can't remember whether that occurred or not.

It's due to this info that I blame the Puebla factory for the faulty decal codes. It's slipshod, and could have been corrected, and not something that I think would be tolerated in Europe, but clearly it was ok in Mexico throughout the entirety of the Mk3 tdi production.

Most of the B4s were assembled in Brussels, Belgium. While the 'W' in the first place seems to have originally been to signify West Germany, it later sort of became "Greater Europe" instead. Because even the Slovakia- assembled cars (T'reg, Q7, etc.), Austrian-assembled cars, Portugal-assembled cars (Eos), and all the Belgian-assembled and I think even some Polish-assembled cars all carry the 'W' in the first digit. VAG breaks down which plant in the VIN, though, I forget which digit. But Turkey is different (first gen TT came from there, as do many little Ford Transit Connects, Promaster City (Fiats)). Great Britain is different. Not sure about Spain or Italy, but they may have their own code...Italy probably does anyway.

From what I've seen / read ALL of the B4's came from Brussels. I don't think I went that far above but after I wrote that post above I did a little more digging and I don't see any other factory mentioned. And yes, I think it's now technically a Europe thing or a semi-continental since there was no attempt to differentiate for a lot of it.

This is what I was able to find a while back, I think it was written in 2016 so at this point it's considered quite old.

1 or 4 = US
2 = Canada
3 = Mexico
J = Japan
K = Korea
S = England
W = Germany
Z = Italy

Steve

 

[oilhammer]

I know about the labor issue in the early '90s. That really didn't have anything to do with the cars we are discussing. And having purchased five Volkswagens brand new (and PDI'd many others) I can assure you, Mexican assembly is at the very top of QC. The Puebla plant has actually won many internal awards. It was tasked with the rollout of the New Beetle in 1998, and was the ONLY place that ever assembled them, and they were sent back to Europe for retail sale (as well as some other models... like the original Beetle). Of my five new cars, all three of my Puebla cars were 100% perfect. Both my German cars (one from Emden, the other from Wolfsburg) had various QC problems. And for good reason. EVERYONE in the Puebla plant speaks Spanish. The German plants are a mix of languages and cultures, which only got worse after the fall of the Soviet Union. Prior to that, many Turks were employed in factories. After 1990, there were all kinds of folks. Hard to make certain something is being done correctly when there is a language barrier.