im looking at this 84 318i for another car. the guy im wanting to buy it from says the engine wont start right now. he rebuilt the distributor but doesnt know how good of a job he did. but he said with it in, the car would start and run, but idle at 2000rpm and thinks theres a vacuum leak. has anyone else had a problem like this or know of a fix? i dont want to buy it and be stuck in a huge project. i need this to be as cheap as possible...
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FWIW
My mother-in-law had an 84 318i beater a few years ago, at one point it had a 3000rpm idle. Turned out to be the idle control valve, replaced it and all was well...besides the gear linkage, missfire, slipping clutch, bad tranny, cold start issues, warm start issues, keyed paint and so on.sigpic -
well this guy claims he did something with the icv, but who knows. another guy told me you can clean em out somehow. doubt thats true though. i looked at an eta with a messed up icv and what it did was go from 500 to 2000 rpm. all jumpy. this guys saying it stays idling at 2000.
Originally posted by 10/10ths View PostComment
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It's been a long time but I THINK we tried cleaning the icv as well...but in the end we needed a new one.
If you dont want to be stuck with a huge project you should be a bit weary of buying an 84 318i that doesn't already run, and well at that. Unless it's super cheap, $200-500sigpicComment
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yea its $500. ive only done engine work to my m20, so the m10 would be a bit of a change. im also looking at another e28 but its a 528e for the same price. but he said the engine is fine, just idles bad. said he either needs a new distributor and something with a vacuum leak to get it running right. its atleast a 5 spd though...Originally posted by 10/10ths View PostComment
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Originally posted by jw 325ic View Post
lol, DONT buy a 528e!!
Actually, the only one I have experiance with is an automatic, but you still dont want one. It's hard to believe it's a BMW, about as fun to drive as a wood-panel station wagen.sigpicComment
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Originally posted by 10/10ths View Post
haha i figured. but its for my fiance as her daily to get her to and from work, clean and sell. but if i get an e30 ill keep it a bit longer.
im just wondering if its just the idle control valve, i can find one at a junk yard for next to nothing, but otherwise id hate to spend all the time in the engine bay trying to diagnose the problem. i also dont wanna spend all sorts of money trying to get it running again.Comment
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Well, if it's not an obvious vacuum leak, and for it to idle at 2000rpm it would be, I would try the icv first.
So just a beater type car is what you have in mind?sigpicComment
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yea, but i still wanna clean it up and sell. i cant see an e30, or any bimmer lookin like a pos. especially if i or my fiance or a family members driving it. my ma even drives a mint condition e34 lol. bros in an e36. fiance had a nice e28 but it got hit so this is the replacement.Originally posted by 10/10ths View Post
basically just a good running daily driver, but clean and simple things done to it.Comment
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I asked essentially the same question on the yahoo groups m10 -318i board and here's the answer I got. In short, don't do it looking for an easy fix!
"Anyone working on a 24 year old E30 fuel injection system needs the Robert Bentley E30 Repair manual and RB’s Bosch Fuel Injection manual from the same era – plus a digital multi-meter. The manuals and multi-meter as good as a BMW shop fault computer.
Have the engine compartment thoroughly cleaned with water/steam (wrap any electronics to prevent water contamination) to eliminate any dirt that might be interfering with things. Dirt/oil/grease will seal air leaks or interfere with electrical operations one day, allow them the next.
To ensure dependability on a 24 year old fuel injection system, replace ALL rubber hoses and ALL gaskets wherever unmetered air can leak into the motor on the motor side of the air flow meter, or independent of it. And not just for the air/fuel systems. Replace the brake booster hose, all the oil hoses. Remove and throw away those ANCO hose clamps that have accumulated over the years and put real BMW ones on – properly sized against the BMW parts manual – instead. A new ring seal on the oil filler cap and a new valve cover seal aren’t utterly necessary on the M10 motor, but you’ll feel better in the morning after you’ve done that. Don’t overlook the distributor shaft seal. With the motor at operating temperature, station 2 friends with fire extinguishers on each side of the engine compartment and you squirt a little starter fluid around the intake manifold gaskets. Any change to engine idle or running characteristics noted as the stuff evaporates signals an air leak there.
The rubber hose FROM the air flow meter to the throttle body cracks on the bottom and around the clamps over the years. If yours is 24 years old, throw it away and invest in a new one. You might not even see the crack that’s letting in air. Make sure the clamps are BMW-authentic, too.
Invest in new fuel line hoses as well. If you can smell gas in the engine compartment, one is cracked somewhere. Old BMW fuel hoses are a fire hazard.
Once you have an absolutely airtight motor, you have eliminated about 20-30% of your potential intermittent drivability problems on the E30 M10 EFI system. Move on to the electrical stuff.
24 year old BMW wiring harnesses have been hammered all those years by heat, vibration and corrosion.
Before doing any of the following electrical system work, disconnect the negative side of the battery.
Check every wire that has anything to do with the fuel injection system or drivability for continuity. Flex the wiring while putting the multi-meter on them. Frequently, an older BMW wiring harness wire will crack inside its insulation and continue to pass current part of the time, and not at other times. The wiring to the oxygen sensor is a frequent culprit. Any soldered connection is suspect on a 24 year old BMW E30. The solder cracks and you’ll never see the defect by eye. If you are good at it, re-solder all connections you can reach yourself, or ask a friend to do it. Pull the circuit board out of the instrument cluster and take it to a professional electronics repair shop. Have every soldered joint redone on the circuit board as well. They frequently cause problems with invisible cracks after all the years. (You can have the shop rig a snap in/snap out holder for the NICAD batteries while it is at it. Never have to fuss with re-soldering the batteries while replacing them again.)
Thoroughly clean every wiring connector with a brass brush and connector cleaning solvent. Dremel Tools are wonderful for the hard to get at places. Test the connectors on the multi-meter. Make sure the connection is tight and the plastic and metal components aren’t broken or missing. Eliminate any corrosion damage that you can see. Splice in new connectors if any appear defective. Wires fatigue at connectors quite often. Pull the fuse box and completely clean all the connectors in and around that, too. Chances are you’ll break some because they are corroded. Replace. Re-solder. Lots of older BMWs have cracked or crumbling rubber boots that no longer protect connectors. Replace them if that’s the case.
Using your RB Service Manual’s electrical wiring diagram, find every ground point on the motor’s wiring harness, including the main ground on the intake side of the motor. Clean all mating surfaces to bright metal with a brass brush and emery cloth, then re-connect and protect with suitable dielectric or other compound, if you live close to the ocean or in a really wet climate (you said Seattle??). Don’t forget to get into the computer compartment under the glove box and clean all connectors to the car’s brains. Be very careful to disconnect power to the battery and ground yourself before touching the computer, however.
Don’t forget to check your distributor. A worn distributor causes considerable erratic motor operation, including bad idle. Have it bench tested by someone not interested in selling you a new distributor.
The E30’s EFI sensors are pretty simple to check, though not prone to defects. With the RB and Bosch manuals, you can check sensor resistance against given values. Throw away the components that you don’t like.
Once you have addressed your air and electrical gremlins, you have eliminated at least 75% of the E30 M10 EFI system problems. If there are still problems, your RB Manual and Bosch Fuel Injection guide can help you work through them.
Good luck! Enjoy!"Comment
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