waterpump belt

[SethB]

Are spark plugs put on in wrong order ?

Highly unlikely, unless the engine feels like it's trying to shake itself out of the car.

Hard to troubleshoot without more detailed symptoms. Do you lose power when applying the gas after the shift, when letting off the gas to shift, etc? Almost sounds like a bad ground or something's shorting somewhere under accel or decel. But again, try to pinpoint exactly what inputs (gas, brake, letting off the gas, etc) and timing (before/after shift, etc) are happening, and what exactly happens (no power, rpms low, rpms but no power, etc).

[Sonny]

Are spark plugs put on in wrong order ?

[DIPLODICUS]

Check your fuel pressure and spark plugs. Also invest in a multimeter to test electrical components before just throwing new parts at the car. The bentley has the specs listed for things like the coolant temp sensor, etc

[EbzyyE30]

https://www.youtube.com/watch?v=xhk7x58XFkE

if you watch this guys video this is almost identical to what happens, there are no comments on the video and this is not my video but this is exactly what happens.I also realized that 3rd gear was just where i found it more common however from driving the car more, it happens in all gears if i don't granny shift it at 3k in every gear.

[the_eskimo_wonder]

Definitely not clutch related, and definitely not cold air intake related.

I would probably just start checking everything ignition related. Maybe crank position sensor? Honestly I'm not really sure what would cause that kind of violent cutoff only at that specific condition.

[325e '87]

The fuel pump will not energize unless the engine is turning. The buzz you may hear under the hood when you turn the ignition on is likely your idle control valve.

Search here for aftermarket air intakes. People have proven that most all of the bolt on cold air intakes actually cost you horsepower. The stock bmw filter box is the best.

A violent engine cut off at wot in third gear is hard for me to imagine, there’s nothing unique about third gear except its the best gear to play with max engine power on public roads. I wish i could help more.

[EbzyyE30]

Blue temp sensor and O2 sensor are both great parts to replace when diagnosing a rough running engine. I would go Bosch on both and both can be had on Amazon or RockAuto for about $80-90 total.

Aftermarket headers and an intake won't have any real effect on air/fuel mixture. Definitely don't need to tune for them. But is there anything else that's been done to the engine?

Elaborate on "in 3rd gear the car loses everything". That gives us no details on the problem at all.

Yea the blue one i bought was bosch but it was not 80$ i got it for 20$ so im quite happy bout that. also i thought that if u do aftermarket intake it takes a substantial amount of air in compared to stock, so there might be too much air for the mixture, resulting in a backfire. what happens in third gear is at 3500 rpm the car lurks and jumps forward and loses all power for a split second, feels awful. i took my dad for a spin and showed him what it was and he said theres no way its anything to do with clutch but he's just as confused as me.

Question: when starting your e30, does the stock fuel pump make noise like it's turning on?

thanks in advance.

[the_eskimo_wonder]

Blue temp sensor and O2 sensor are both great parts to replace when diagnosing a rough running engine. I would go Bosch on both and both can be had on Amazon or RockAuto for about $80-90 total.

Aftermarket headers and an intake won't have any real effect on air/fuel mixture. Definitely don't need to tune for them. But is there anything else that's been done to the engine?

Elaborate on "in 3rd gear the car loses everything". That gives us no details on the problem at all.

[EbzyyE30]

3rd gear is the most glorious feeling when the engine is running well.

Maybe you should freshen up the fuel injection. New temp sensors, oxygen sensor, fuel pressure regulator, and pop out the fuel rail and check/clean up the injectors. Fuel filter too.

Check replace the distributor and rotor, spark plugs, throttle switch, and check that the AFM board isn’t worn through its swipe contact.

Sounds about right, thats what i will do, which temp sensors should be changed? i know i have to change the coolant temp sensors would that mess with fuel injection? Thanks for your input as-well!

[325e '87]

3rd gear is the most glorious feeling when the engine is running well.

Maybe you should freshen up the fuel injection. New temp sensors, oxygen sensor, fuel pressure regulator, and pop out the fuel rail and check/clean up the injectors. Fuel filter too.

Check replace the distributor and rotor, spark plugs, throttle switch, and check that the AFM board isn’t worn through its swipe contact.

[EbzyyE30]

Don't over complicate things mate.

Inspect the front belts (water pump, alternator, aircon, power steering), if they look a bit cracked and old get new ons. if they look alright tighten them up as my my instructions above.

timing belt - figue out of the odo is broken. if it is then id be looking to change it when you can. if its not broken then happy days, few miles left in it yet. I've had a timing belt break on me, complete destruction of engine. nothing salvageable. its pretty rare, but when it happens its engine in the bin time.

Ok so its been a while, been working on the car and studying for finals, i ended up tightening the belts everything is well on that behalf! the Odo works ive taken the car out for gas and driven it on some backroads. there is still some problems however. I have a leaky clutch master cylinder it only leaks a bit and im looking to just replace it next winter when i cant drive the car anymore ill just keep fluids topped up. the last thing that bothers me the most is at high rpm or under load im not really sure when it happens. sometimes i can rev it up till 4k/4.5k in second and shift to third everything will be smooth but if i step on it in third the car kinda loses everything. i dont know if its fuel related or clutch related cuz im pretty sure i have a good clutch even had the old man look at it so i dont think its slipping but again im not sure.

Need some suggestions! maybe seafoam if the fuel system is gunked up?

[EDIT] Did some research just now and it has come down to a backfire? first time it happened i thought i blew the motor i jumped out the car and looked under. but why does the car lose all power?
[EDIT 2] did some more research, pretty sure the car is running lean and it is hesitating. previous owner installed headers and different air filter from Kamotors. should i tune the car/ can it be tuned on stock ECU.

[e30davie]

Don't over complicate things mate.

Inspect the front belts (water pump, alternator, aircon, power steering), if they look a bit cracked and old get new ons. if they look alright tighten them up as my my instructions above.

timing belt - figue out of the odo is broken. if it is then id be looking to change it when you can. if its not broken then happy days, few miles left in it yet. I've had a timing belt break on me, complete destruction of engine. nothing salvageable. its pretty rare, but when it happens its engine in the bin time.

[EbzyyE30]

I do have the bentley manual previous owner seemed like he took care of it, i do think the belts are stretched, ill read the manual and see what it says.

Called the previous owner he told me that he doesn't exactly remember exactly but he thought he did it at 180/184k miles the car now is at 189 but im unsure if its broken odo or not, either way i dont think the timing belt is bad i just think the serpentine belts are loose at this point.

[EbzyyE30]

Belts are stretched probably, change them out it's pennies. Do you have a Bentley manual?
Order one it's a must

Blunttech.com, email them and ask for a tune up kit , the best in the business!

I do have the bentley manual previous owner seemed like he took care of it, i do think the belts are stretched, ill read the manual and see what it says.

[SethB]

The belt tightening mechanisms on these are a bit tricky compared to most. Find the adjustment mechanism above the alternator, there is Locking nut on the back of it, and you turn the nut on the front and it sort of runs along some teeth on the adjustment mechanism. Then once its tight you do the locking nut back up again. I made the mistake of trying to turn the front nut without loosening the locking nut on the rear and stripped the teeth the nut. Don't do what i did.

Its a pretty ingenious tightening mechanism but yer if you don't know what you are looking for easy to damage by mistake.

+1

It's probably worth reading through the whole thing, but start with steps 13-14, then 17-19:

https://classicbimmerbits.com/e30-how-to/e30-accessory-belt-replacement/