Engine number doesn’t match hood sticker

[Quaylon]

While ordering parts to replace the hoses I disturbed while replacing the water pump and AOS on my ‘99 C2 manual convertible, I discovered that my engine number doesn’t match my hood sticker.

I placed an order with Atlanta Perimeter Porsche and included the VIN number with the order. I received an email a few hours later stating that based on the engine number I needed a different numbered part for one of the hoses. They said that sometimes the parts are based on engine numbers. They were kind enough to include the engine number they located. That got me curious...

First, I checked the hood sticker and the numbers didn’t match. My curiosity increased to cat like levels... so I crawled under the car armed with cleaning solution, a brush and a phone. After several minutes I had images that I could read the engine number from. It doesn’t match... neither the hood sticker nor the number from Perimeter.

Is there a way to determine the “in service” date from an engine number? I have service records from the dealer that the previous owner used, dating back to 2002 but there is a 3 year, 20,000 mile gap. I have nothing from the original owner, 1999 through 2002. Nothing in the records even hints at engine issues let alone replacement.

I am going to pull a carfax. Any other suggestions?

Thanks,
—Q

[DBJoe996]

What is the engine number? If it has an AT in it, then it is a Porsche replacement engine. Otherwise, the engine could have been replaced with a used donor engine at some point in time.

[B3DAWG]

Be thankful. Daniel at Perimeter Porsche Parts is very proactive in going the extra mile and saving you a lot of trouble. Think about it, if he hadn't checked your VIN and engine number, you'd end up with parts that don't fit perfectly and then you'd have to return them and try to locate replacements. They've done it for me several times.

Re: the engine serial number.

Mine doesn't match the VIN tag either and so it's highly probable that Porsche replaced it during the warranty period.

My hood tag states my original engine was s/n is M96/03-662-0960-10, but the actual engine number in the car is M96/03-662-0184-7

The middle number is usually what you need to identify the year of manufacture. In my case, 662 is for "2002".

[Quaylon]

I should have included the numbers in the original post, my bad...

Hood sticker says: 66X69600
Perimeter says: 66X06108
Engine stamped: 66X15987

I’d really like to know when that engine went in service and what model variant it came from.

Thanks,
—Q

[Quaylon]

B3freak: Don’t get me wrong, I’m thankful for the awesome service I get from Perimeter. I wish more online outfits did the same. As you said, a couple of emails in a few hours saved me days of delay and dollars of shipping costs.

I just left wondering if the miles on my engine match my odometer...

Thanks,
—Q

[B3DAWG]

I should have included the numbers in the original post, my bad...

Hood sticker says: 66X69600
Perimeter says: 66X06108
Engine stamped: 66X15987

I’d really like to know when that engine went in service and what model variant it came from.

Thanks,
—Q

Correction to my last post - 66 is designated for both mk1 and mk2

Based on all the info I have at my finger tips, that's definitely a 1999 3.4L Mk1 engine.

Based on the Porsche directives -

66W = 1998
66X = 1999
66Y = 2000
661 - 665 = 2001 through 2005

[B3DAWG]

I should have included the numbers in the original post, my bad...

Hood sticker says: 66X69600
Perimeter says: 66X06108
Engine stamped: 66X15987

I’d really like to know when that engine went in service and what model variant it came from.

Thanks,
—Q

Well, IMHO, I wouldn't beat yourself up with it. First things first, send Daniel a note and picture of the actual serial number and he'll cross reference the right parts for you. While you wait, you may want to pull the Carfax and see if it notes the dealerships that did the service over the years. Then, by process of elimination, you may want to contact each one and see if you can identify which service center handled the engine swap. That will give you an odometer reading when it was installed. But be mindful that Porsche dealerships don't share data on cars. That was the case in my car. They could only give me information of on what Hennessy Porsche did to the car, NOT what other Porsche dealerships (e.g. Jim Ellis) did.

[Dr_Strangelove]

Mine doesn't match the VIN tag either and so it's highly probable that Porsche replaced it during the warranty period.

My hood tag states my original engine was s/n is M96/03-662-0960-10, but the actual engine number in the car is M96/03-662-0184-7

Interesting, b3. So we can be lead to believe that someone replaced your engine, though not through Porsche? Looks like you got one from further up the production line. My understanding is that any replacement engine from the factory would have been stamped "AT".

[B3DAWG]

Mine doesn't match the VIN tag either and so it's highly probable that Porsche replaced it during the warranty period.

My hood tag states my original engine was s/n is M96/03-662-0960-10, but the actual engine number in the car is M96/03-662-0184-7

Interesting, b3. So we can be lead to believe that someone replaced your engine, though not through Porsche? Looks like you got one from further up the production line. My understanding is that any replacement engine from the factory would have been stamped "AT".

Yea, anything is possible. I haven't search who, what, when, and where on my engine. I've heard the "AT" tossed around heated forum discussions, but I'm going with Raby on this one and you just can't trust Porsche directives on engine replacements. Things don't always follow a logical numeric pattern. Maybe I'm wrong here.

[DBJoe996]

I found this over on Renntech