# 84-85 vs 86-87 325e mpg



## taro (Aug 25, 2004)

hello, 

i've been looking into a 325e for commuting purposes. i bought jeremy walton's 3-series enthusiast's companion and noticed that the fuel economy listed for an 84-85 325e was 27city/38hwy and 21/28 for an 86-87 325e. the only differences i've noted between the two are a final drive ratio of 2.78 for the 84-85 and 2.93 for the 86-87 and the 86-87 being a few pounds heavier. 

is the fuel economy for the 86-87 that much less or is this a typo? thanks, taro


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## JamesSpot (Mar 4, 2003)

*They are different*

The "e" signifies the "eta" engine. It had higher torque, less Hp, and a lower redline than other BMW motors in the days when fuel economy became a top priority. They are not as desireable as track cars as they run out of breathing room as the RPMs come up and do not pull as strong as other BMW motors, but is a perfectly fine engine for normal driving.

I had a neighbor who had a 528e, a very nice sedan. I wouldn't expect to get quite those fuel mileage numbers on an older car, but the "e" motor will return better mileage.

From another web site:
"The US market saw many of these cars arrive in "eta" form. The 2.7 litre eta engine was designed to use less fuel while still offering good performance, surely only Americans could ask for a 2.7 litre economy engine! This was a fairly durable engine whose only failing was its unwillingness to rev at high speeds."

In Europe, taxes are based on displacement, which is why it seems unfathomable to Europeans that the US market would want a large motor with limited horsepower. They want tiny engines that can still pull a car 120 mph. Since we had a 55 mph national speed limit when the "e" engine was designed and gas prices had quadrupled, the US market received a unique motor.


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## taro (Aug 25, 2004)

James,

thanks for the response. yeah, i wish i could go for the 325i(s)s, but in order to justify a third car, it's got to be as economical as possible. coming from a suv though, i'm sure the 325e will feel pretty good.  

i'm debating between the 84-85s and the 86-87s. ideally, i'd like to get the 86-87s with abs and standard a/c, etc. (it'd be great if i could score a nice 325es), but if the difference in fuel economy is significant, i'd be willing to forego abs. thanks, taro


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## JamesSpot (Mar 4, 2003)

*318i or 318ti as an option?*

I've seen some great 4 cylinder 318i's for sale for around $10k with 60-70K miles. That would have all the economy of the "e" 6 cylinder, would still rev, and would be in the newer E36 platform. They were pretty reliable sporting cars and have all the looks and handling of the E36 with a less powerful engine.


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## The Roadstergal (Sep 7, 2002)

The 325e is a nice torquey car, easy to maintain, very good around-town commuter. I had an '86 and got 28-30mpg around town. I'd go for the '86-'87.
I dunno if it's how they all were, but mine was metered a little rich, and I leaned it out. That might also account for the different economy numbers.

Re: E36 318 - the E36 is significantly heavier than the E30. I prefer the latter.


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## taro (Aug 25, 2004)

thanks for the responses. 

James, $10k is more than i was hoping for. the 325e(s)s seem to be going for $1000-$3000 on average on ebay. 

Roadstergal, just out of curiosity, what made you realize it was running rich? was it giving you any problems (e.g., spark plugs, exhaust)? what did you have to do to lean it out (throttle body adjustment, different injectors, new chip)? please be patient, i'm learning . also, what other memories do you have of your '86? any major problems, etc., etc.? sorry for asking so many questions. 

thanks, taro


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## RChoudry (Jan 13, 2002)

got my 325es for $2500. so far, 3000 miles with average mpg of 25 combined city/highway.

love that damn car.


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## taro (Aug 25, 2004)

sounds like the 86-87 325eta has some well earned supporters out there. i saw one yesterday that looked brand new, not for sale though. does anyone out there have any experiences/preferences between the 84-85s and the 86-87s? thanks, taro


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## Paul C (Aug 29, 2004)

*'85 325e gas consumption*



JamesSpot said:


> The "e" signifies the "eta" engine. It had higher torque, less Hp, and a lower redline than other BMW motors in the days when fuel economy became a top priority. They are not as desireable as track cars as they run out of breathing room as the RPMs come up and do not pull as strong as other BMW motors, but is a perfectly fine engine for normal driving.
> 
> I had a neighbor who had a 528e, a very nice sedan. I wouldn't expect to get quite those fuel mileage numbers on an older car, but the "e" motor will return better mileage.
> 
> ...


 I recently sold an '85 325e which got 25 mpg city and 35 mpg highway. Very good auto for anything but racing. Very solid for a 20 year old. The buyer had been looking for this paticular car for awhile. He had one years ago and wished he had kept it. Even though mine was in good shape, he intends to do a complete restoral, and keep it for life.


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## The Roadstergal (Sep 7, 2002)

Sorry, I was out of town. The ICV is a problem on the older 325s; it goes south and takes your idle with it, often the driveability of the car. Cleaning it sometimes helps, but you often just need a new one. Also, all of the E30 6-cylinders have timing belts that need replacing every 60K miles. That's usually combined with water pump and coolant service.
They also tend to have the SI batteries die; that makes the service countdown go down really fast, and often makes the gauges stop working. Easy to fix; pull the board and replace the batteries.

I had a minor vacuum leak (no driveability issues, just noticed a crack in the boot), and noticed after I fixed it (repairing an artificially lean condition) that my mileage dropped and I no longer had a lean grumble when coming off of the throttle. I messed with the AFM. You're not supposed to do that.

It had an aftermarket (ANSA) exhaust, which rusted out in short order. For E30s, you can't beat stock exhaust systems. I got an i cat and muffler (six-to-two instead of six-to-one) off of local guys; it took a little enlarging of the holes mating to the exhaust manifold studs, but other than that it was a direct bolt-on and sounded good and ran well. I did have to replace the oxygen sensor at some point, but it went on the Miata, too, at 120k miles. It passed emissions with flying colors.

Other than that, nice car.


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## taro (Aug 25, 2004)

thanks for the continued replies...

Paul, just out of curiosity, do you mind sharing what the going rate for the '85 was? 

RChoudry and Roadstergal, do you have any estimates of what kind of mileage you are getting or got on the highway?

Roadstergal, thanks for the description. these things sound like tanks. looks like on the 86-87s, the onboard computer was not on the base models. are these a problem area in a similar manner as the SI. i've become rather paranoid about electronic gizmos lately. thanks, taro


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## The Roadstergal (Sep 7, 2002)

The SI board is part of the instrument cluster, seperate from the OBC. You can swap a nine-button (vaguely useful) OBC into the base models with little effort. I was getting 28-30 'round town; didn't really take any long trips for just-highway mileage on a tank.

I did have the SI battery problem and a nonrunning odometer when I bought the car, so I got a used cluster from a later i, cleaned it up, and stuck it in. Pros - it worked fine, the gauges were accurate, and the later boards came with lithium batteries that were longer-lived than the earlier batteries. No problems after that. Cons - the fuel cutoff on the eta is ~5K RPM, which is halfway up the i tach. I had to remember that...


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