air intake sensor issues
 

I've got a '74 914 1.8 and i just rebuilt the engine and put it back in the car. The problem is with the air intake sensor thats on top of/in front of the filter box.

Here's the problem:
-When the AIS is UNplugged, the car starts up fine, and runs, but fouls plugs in about 5 minutes (running extremely rich?)
-When the AIS is plugged in, the engine will not start. It will turn over and occasionally it will fire once or twice but it never actually runs.
-The second is not COMPLETELY true. ONE time the engine started with the intake sensor plugged in, but the engine revs started climbing, and fearing for the life of my newly rebuilt engine:eek: i shut it off. Immediately after that i tried it again and it only fired once or twice.

PS: I have checked the resistances on the sensor and my dad is an electrical genius, and as far as he can tell the electronics part of the box itself is in 100% perfect shape, so the problem is somewhere OTHER than the box or the plug.

I am going to check for vacuum leaks tomorrow, but any other seggestionts on what to do owuld be greatly appreciated.

THANKS SmileWavy

actually im 17 and..i got mine for free too. Thanks uncle dave! mines a 2.0 tho! neener neener neener

Congrats....now you just need to learn how to spell PORSCHE :)


If the 1.8 still has the L-jet injection, you have an AFM, not an AIS (I lied, the AIS is inside the AFM) Air Flow Meter

The AFM must be plugged in for the car to run, what happens is when the motor turns over while trying to start it, a flap in the AFM opens, which in turn activates a dual relay near the battery which turns on the fuel pump and also supplies voltage to the injectors (injectors fire when grounded inside the ECU)


Sounds like you have a major leak in the hoses or the oil fill tube....1.8 motors do not like vaccum leaks at all....once you fix those, it'll be nice little ride....

hmmmm free 914? I've had three free 914's and I've had to turn a few other offers down.... :)

thanks for your help. I didnt get to check for the vacuum leaks today, but it sounds like that most likely is the culprit.

by the way, where did i spell porsche wrong? :p

well i spelled pretty much everything else wrong though... :o

Well I Got Mine When I Was 18,Back In 1977 It Was A 1971-4,Saved Up for It And Payed $ 3100.00 For It. The Funny Thing I Still Got The Car.... The Only Thing I Regret Its Not A Six
Happy Holidays,914

It is actually a 914 ... not really a Porsche. ;) get used to it. Time for a reallity check. in similiar condition, most vintage VW beetles are worth more than a 914 1.8l.


Merry Christmas

I feel like a dumbass :o. I cant figure out where the hose that comes off the charcoal canister plugs into the fan shroud. Is it on the top? bottom? left? right??

By the way, norustscott, i reported your post. I put a thread together because this is my first real undertaking of a major project on any car of any kind. I posted to get some good, courteous tech advice, which i got from everyone else but you. Have a nice day!SmileWavy

Depending on the year of the car, it could be on the right side (passenger's side) of the fan shroud itself, or on the engine tin.

--DD

Dude, you're 17 - take a chill. I didn't appreciate the "reported post" email you sent me on this...

-Wayne

Maybe he is missing the "H" on his engine lid.

GAWD Wayne - you do have a life - you're beginning to sound like Dave - now what's really spooky is if you start to look like him:eek:

As far as a vintage VW being worth more than a 914 (any model), one cannot account for the mass publics ignorance and stupidity. Ah Yes, I'm gonna pay lots of dollars for an ill handling death machine.

As far as reporting posts, yousaidpoo, you had better get a thicker skin of you're gonna play here. You will get great advice and have a trememdous knowledge base available to you, but sometimes we all get a little frisky with our answers becasue humor (sarcastic at that) has it's place here. We're all sicko's because we own and love the bastard child of Karmann & Porsche. Personally, I'm just a sicko anyway.

As far as knowing where various hoses go, I'll tell you what I tell anyone who buys or gets a car - "GO BUY THE FRIGGEN BOOK - READ IT - AND THEN ASK QUESTIONS ABOUT WHAT'S NOT THERE". Also, if you look at the Tech Articles on PP - you're gonna find some answers there too! And, if you're gonna ask why I said this - here's the answer - I raced for may years, built a lot of cars, most of what I knew came from research, books and a lot of errors that cost money. NO ONE gave me the info to win for free.

All that know me realize this is a kind post. If this were Sunday Morning, I would be the lawnmower and you would be the grass. So keep posting, take the humor in stride, learn a lot of crap and you will eventually join in the fun and frivloity as soon as your brain develops.:)

Now, if I could just remember why I wrote this post.

yousaidpoo, 914's and paintball. Gee, sounds a little like me. Been playing for years in So Cal. Anyway, take Ron's advice it's great advice. This is the best place to be for 914 advice. I just finished a full rebuild and without the help of everyone on this BBS, I can honestly say, I would have given up a long time ago :)

Rod

"As far as reporting posts, yousaidpoo, you had better get a thicker skin of you're gonna play here."

Wait till you say something really uninformed about the type 4 and Raby let's you have it.

And the way people treat each other in here is awesome compared to the way an improperly tuned teener will treat you.

BTW, good luck with your L-jet.:)

yea, i kinda flipped out. i was really frustrated because i had been working on the car all day and was really frustrated, so i came back to this forum to see if anyone had added any more helpful advice and i had gotten a bunch of stuff that wasnt helpful and i took it the wrong way. my bad. i'm usually a pretty cool-tempered guy, but being as frustrated as i was (i'm sure most of you have been there) i just over reacted

914's are incredibly frustrating, and a lot of fun. Depending on their mood. If there was ever a car that was more like a woman than any other, it could be a 914.

Sexy, temperamental, handles great, and a little slow. But could we live without them....not in a million years.

Can I get an AMEN?

By the way, Dave its a 1974 USA model, if that helps determine the hose location. There's a spot on the front passenger side of the air housing that the hose fits snug over, but the hole for the air to come out is only about 1/8 of an inch, so im not sure if thats right. Any help would be appreciated. I just dont want to start it with something plugged in wrong and serious screw it up.

And Ron, I have a Haynes manual on the car and i have the vaccum hose diagrams from the site, but all they say is that the hose goes onto the fan shroud, it doesnt say where, because, as Dave said, it varies by year, and none of my resources are specific to the 1974 model year.


-is there any way i can take that poll off:confused:

Just for the Record, I m 15 and my 914 is almost fully restored. Now what up!