30 MPG 1.9 Caddy...Help?.. Anyone?

[Anxiety]

Hi all, I'm new here. I bought an '81 Caddy about a month ago. The guy i bought it from told me it got about 38 MPG. I just filled it up again and around town driving I'm only getting about 30 or less. A little about the truck; the guy i bought it from says it has a '93 1.9turbo motor in it  minus the turbo. He said he bought the motor brand new about 100,000 miles ago. Also he said he just put a brand new injection pump on it. The pump looks to be new. Within a week of buying the car, one of the steel injector lines cracked while I was driving and I have replaced that. I also replaced the return lines from the injectors as they were leaking. One of the nipples on an injector is leaking. When you pull the rubber hose off it is loose. The injectors are mismatched. One of them is visually different from the rest and some look newer than others. The car seems to run fine. Starts right up and seems to have plenty of power. Runs pretty smooth and doesn't seem to misfire. I also replaced the air filter after I checked my mileage and found it was pretty nasty. It looks like it was soaked with diesel and/or oil. The car doesn't smoke except when you gun the engine in neutral it will give a very slight black smoke. I pulled the breather line while it was running and it has minimal blowby. I believe the engine to be in good shape but I'm thinking maybe the timing is off and probably the injectors need rebuilding/replacement?

Any suggestions on where I can start? How about a bottle of some type of injector cleaner? I know for sure i have to replace one injector, should I just order a whole new set? What's the price of new vs. rebuilt?

Also, I'm not exactly sure where to find the engine code so I know what injectors to get. If anyone could show me a picture of exactly where I'm supposed to be looking I would appreciate it.

I'm not a novice mechanic and I'l be getting the timing tools soon. I've really been wanting one of these trucks for a long time. My buddy had a Rabbit deisel in high school and that thing got 48 MPG. I was really hoping to have a pickup that gets that same kind of mileage. I trust all the things i was told about the truck before I bought it. I bought it from an older guy, a high school teacher. He seemed pretty honest. And if not I know where he lives. :mrgreen:  Thanks in advance for any knowledge you might share. Andrew

[jtanguay]

bad/leaking injectors can definitely screw up mileage.  now the fact that your air filter was soaked in possibly diesel is a bit odd... i would drive it for a bit and periodically check the air filter and see if the new one becomes soaked/contaminated as well.  if so then there might be some nasty blowby at higher rpm's.  

have you revved the engine while having a look at the breather hose? don't aim at your face!  :lol:

[Op-Ivy]

Did he say 38MPG Imperial or US? 38 Imperial is about 31 US. So he might not be trying to screw you.

Still though, you can get a bit better than that. Try searching the forums. This has been covered MANY times!

EDIT: Oh, and welcome!

[rabbitman]

I think one injector on that motor is always different from the rest. Is it just a little longer than the rest?

welcome to the forum

[Anxiety]

Thanks everyone for the replies. Sorry it took so long for me to get back on here.

jtanguay : Yes I checked for blowby. Just a very light white vapor when revved up. Looks normal to me. The reason i thought some of the mess on the air filter may have been diesel was because all of the diesel leaking down the front of the block a vaporizing. It was so bad if you drove the truck with the windows up for more than 20 minutes it made you sick. The intake is right there and I just thought some of it could have been from all the vapor over time. Maybe the previous owner tried to clean the filter with solvent or something. I've seen people do that.

Op-Ivy: 38 US. But he drove mostly on the highway and the 30 I get is around town. I have read for hours on here and have not been able to find the most important thing, how do I know which motor is in the car? I have a book but it doesn't show a picture. I think it is supposed to be a # stamped onto a machined surface on the front of the block (side with IP)? I guess i should have put that in the title of my thread about the engine identification. If someone has a picture of exactly what # I'm looking for I would appreciate it.

rabbitman: It's the #4 injector (closest to tranny) that is different. It doesn't appear to be longer just shaped differently at the top just below where the lines go in.

This is the info I need most:

1. Where do I find the engine code, and should it be a stamped # or is it cast into the block?

2. What is the best additive etc. to clean the injectors without removing them?

3. Assuming it is a 1.9 N/A, what injectors should I buy for it? I saw some on ebay for $25 a piece but I'm not sure if they are correct for my engine without knowing what engine i have. I believe the guy is a member of the forums here if I've read correctly. proeth?

Thanks again for the replies and I'll try to check back later today.

[jtanguay]

i think another thing to check is transmission and gearing.  taller gears give better economy at the cost of needing to downshift more often.  (cars with cruise will generally come with a short geared tranny to avoid downshifting and overreving the engine)

[jtanguay]

i just checked this tank and i'm getting about 39 mpg... that is total shiiiite!!! i mean i rip the car whenever i get a chance but still!  :lol: it must be gearing because the tranny feels great for acceleration, but revs too high on the highway.