E28 not so smooth

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beemervader

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Hi,Hope someone can help me out.I recently got a E28 (1984 525 model with short bumper, 5 speed manual transmission). Although the car has to go through some restoration especially body is concerened, it has one hell of a torque.My main concern here is my engines throtlling. At times it's so damn smooth that you can't even hear the engine sound. But sometimes the engine is not that smooth, so much so when you drop to the 2nd gear (example: assuming you're reaching a bump and taking of after) the car will definitely struggle to pick up as if I'm taking of on 4th gear. But this happens only sometimes.There was once when the car actually stalled and i could not get it started at all. I had to call a mechanic to have a look at it. When he checked, he noticed there was no pertol flow from the tank to the engine. The next instance he by passed the fuel pump relay (of course with a short jumper cable) and the engine started. And after that I was able to start the car again and again with the same relay.Now, the mechanic is not to sure of where the problem is. He claims of 2 possibilites:1. The fuel pump relay itself (which I just got replcaed with a new one costing RM 145)2. Now this part I'm not very sure, but he claims that there is an electronic gadget that actually controls the relay activation to the fuel pump. If this gadget gets hot (which he claims is a common problem in E28s), it will not activate the relay and hence disabling the fuel pump. When I asked him if this gadget will actually effect the smoothness of the throttle, he claims maybe possible.Now, the mechanic does not have the mentioned electronic gadget. Although I have replaced the relay, I still have that non smoothness problem at times. There were also instances where the car actually sort of "almost died" (sudden 0 compression on the engine when driving but it picks up again without any intervention, meaning just hit the accelarator and vroom it picks up like I've just pushed started the car).Can anyone help me out here? I really need to find out the actuall problem here.PS: Can someone also suggest on where I can confidently take my car for an entire whole new wiring restoration, right form the engines wiring up to internal wiring? I live in Old Klang Road and don't mind going anywhere in Klang Valley.Rgds
 
Dear BV,
Get in touch with forummer called Wolverine. He has a '84 520i E28. Maybe he can help you. You can PM him for his mobile no. Or you can come to Klang tt tonite, he'll be there.
Cheers :D
 
Originally posted by beemervader@Jun 23 2005, 09:09 AM

My main concern here is my engines throtlling. At times it's so damn smooth that you can't even hear the engine sound. But sometimes the engine is not that smooth, so much so when you drop to the 2nd gear (example: assuming you're reaching a bump and taking of after) the car will definitely struggle to pick up as if I'm taking of on 4th gear. But this happens only sometimes.

2. Now this part I'm not very sure, but he claims that there is an electronic gadget that actually controls the relay activation to the fuel pump. If this gadget gets hot (which he claims is a common problem in E28s), it will not activate the relay and hence disabling the fuel pump. When I asked him if this gadget will actually effect the smoothness of the throttle, he claims maybe possible.

I had an e28 b4 but a 520i.
Yr description brought back memories.whenever i drove the car hard and after EVERY long distance driving at hi speed,it would do the same like how you described,loss of power.but power resumes the very next day during normal drives.this went on until i sold it.sorry couldn't be much help.

the gadget your mechanic mentioned,i think,could be the crank case position sensor.just a wild guess.if this fails,the car will not start.no signal to ecu to even deliver fuel to the engine. :dunno:
 
Hi KPC,
Price was RM 3700.0 but already spent and exhorbitant amt of RM 3500 on repairs. And I havent even started on my interior yet.


To the rest,
Guess what, the problem has been solved. It was really bothering me that I had to get it done as soon as I got my posting out on the net.

And you know what, the problem was caused by the spark plug cables. I got the whole thing replaced today with brand new ones and it cost me RM 400 (inlcusive of the cable form the coil to the distributor)

But after changing the cables, pick up has improved tremendously.

Thanks for all your advise......


PS: Sorry to those who got my PM. I'm still new to this group and still toying around with the forum posting.
 
beemervader,

glad to hear u managed to solve ur problem.

let me share with u my experience. the no.2 problem as described by ur mechanic is indeed a common problem for e28s.

when my dad was using e21 323i, he experienced the same problem like urs, sudden drop of power, engine jerked and stalled when hot. my uncle who drives e28 520i also experienced the same problem.

then both my dad and uncle changed the so called electronic gadget, i think it's called ECR (electronic control relay) and problem solved. if u go to chop shop and u said ECR, most probably the wouldn't know, but if u asked for 'BMW punya NYAWA' they'll know instantly.

regards
 
Hi bad4eva,

Appreciate the info.

It makes sense as the mechanic did tell me that "minyak takda naik pigi engine dari fuel pam". And true enough when he bypassed the relay (which i assume to bypass the ECR) it actually started instantaneously

Anyway, any idea how much this ECR will cost regardless new or "potong" and where to get it? Would really appreciate it if you can check it out with your dad and uncle.


Moots,

Probably the same ECR problem with your 520i to.

Hi MTek1318,

Pls forgive my inadequacy on the matter as I'm still new to the forum but what's Klang TT? Is it some beemer owners joint or some workshop?
 
AHH , e28 brings back fond memorie of my 84 520i with zender kit and 16" BBS alloys... have much regrets selling it 6 years ago....bloody reliable cars and good for taking out perdana V6s, .....should have m35'd it!!

OK.if it is running so smoothly sometimes you can count any serious mechanical issues out of the question :D . It therefore has to be either Fuel or Ignition.

Don't complicate thing!! :blink:

It's 99% a fuel issue as that was what caused it to stop the last time. SO No need to make life complicated. Your mechanic has already shown you it it's the fuel relay by bypassed the relay and demonstrating its' runs perfectly. Dont complicate LAH!! no need to second guess & make hypothes it is something else. Cause and effect is the key rule in problem solving.- unless you distrust him so much and if you do you prob should'nt be going to him anyways..

matter of fact I had a similar problem with fuel relays on my older continental cars and now treat fuel relays as a maintenance item ever 7 yrs!! btw Fuel relays lead a hard life as they a mechanical item so changingit on a 20 year old car is not a bad thing.

And yes! fuel flow will affect smoothness and throttleing since an engine is essential a devise for delivering fuel with air and igniting it!!!

your injectors are basically electro magnetic actuator that deliver fuel by opening for a precise time. Without adequate fuel pressure they are unable to deliver the right amount of fuel and deliver it is a right spray patten. Your engine sensor will adapt to the former, but only within limits and after a few minutes of gathering data. in the meantime you engine will run lean (no power, hesitation) and then when fuel pressure is restorred prob rich (surging - no power etc) - until data is gathered again to vary fuel...and the probl the cycle begins again if fuel pressure incorrect.

IMHO best to take to an experience BMW mechanic such as eg M-1, BMW world etc.
 
Originally posted by beemervader@Jun 23 2005, 08:59 PM
Hi MTek1318,

Pls forgive my inadequacy on the matter as I'm still new to the forum but what's Klang TT? Is it some beemer owners joint or some workshop?
Its a beemer owners joint indeed. Some members from Klang Valley gathering weekly in Klang. Similarly you have other gatherings as well. Check the members meetup section for more info. BTW, TT stands for "teh tarik". Cheers. :D
 
Hi MTek1318,

Thks for the info. I might just come over one of these days to Klang to have some TT.


Hi 525iBoy,

Your knowledge on the issue is much to be admired. So as not to complicate things, I will heed your advice.

But I'm kind off baffled that you mentioned nothing of the ECR as qouted by bad4eva. Is there some info u can share with us about it? Cause I m still wondering on why this ECR is needed.


Rgds
 
Originally posted by beemervader@Jun 24 2005, 11:29 AM
Hi MTek1318,

Thks for the info. I might just come over one of these days to Klang to have some TT.


Hi 525iBoy,

Your knowledge on the issue is much to be admired. So as not to complicate things, I will heed your advice.

But I'm kind off baffled that you mentioned nothing of the ECR as qouted by bad4eva. Is there some info u can share with us about it? Cause I m still wondering on why this ECR is needed.


Rgds
I'v never heard of an ECR (electronic controlled relay) and I have the Haynes manual. Perhaps it's a local / or generic. for something else; but term ECR does'nt make sense as arelays are electrically controlled anyway bec: a relay is a essentially a higher amp switch turned off/on by a lower amp switch. I suspect this ECR thingy is often refered to just as a "relay"

Not sure on our BMW, but When a car is running, the fuel pump normally runs all the time with excess fuel being routed back. But some cars may switch off the fuel pump electronically - hence ECR.

A fuel pump relay would hence be needed to switch on the higher wattage, fuel pump, when your lower wattage ignition key is on and it could be this that ECR refers to. I would suspect BMW is the same as all cars used relay for major high draw items, eg lights, ignition etc.

And yes a kaput relay may not work / work intermitent depending on when it is hot/cold/cold/humid/ dry/upset at you etc etc!!! relays cost shoud'nt potong you!! bec I paid about RM120 for an original bosch relay on my Porsche and since BMW uses bosch price should be approx. the same.

BTW: if car is not running smoothly it is almost better to check the normal maintenance items such as spark plugs (incl if they are the right ones & properly gapped), distributor cap & rotor, air & fuel filter, clean engine oil. FIRST because more often than not these are the culprits!!

RM400 for new spark plug wires sound reasonable, considering there are 7 of them:)

Enjoy. :nyehehe:
 
Hi 525iBoy

Thanks for the info. Like you mentioned, I even checked with M Power on the existense of the ECR and they were damn sure that there's nothing else controlling the relay accept for power supply of course.

But ever since I repalced the plug cables, i've been experiencing extremely smooth drive. No more jerks, mild engine rattle and struggle during gear shift.

And as you've mentioned, I've also checked the plugs, cleaned the distributor cap and rotor. Must say that it makes hell of a difference.

Anyway, thanks for the valuable advise. Really appreciate it.


Cheers.
 
no problem,

M20 is still a v. smoothly engine so smoothness is norm

If you have a rattle either due to valves or engine mounting. both cheap to fix.

gearshift is postive but a bit slow.. I have the same "problem"!!

I've installed borsch platinums on my m25 engine and yes it makes things smoother and increases mileage it bit. 7 or 8 heatrange is about right.

enjoy.

btw: what condition was your e28 in when you got it? RM4000 seems a good price.
 
Wow,I've missed da fun... :p

beemervader,

A running condition 525i E28 below RM4k is a good buy...I know a few
forummers here searching at da price range.
First, this is M30B25 engine wif 150BHP n 0-100kmh at 9.8s at ideal state.
Normally, it is said 525i is a 520i wif added grunt.

Yes,u will feel smoother ride if change ur plug cables 2 new 1s.
Btw, it shouldn't hv cost more than RM300.Since ur plug cables r new,
I pressume ur plugs r 2.

4 da rattle...check all ur vacuum hoses first.There shouldn't b any leaks,
even a tiny one.
Second,check ur AFM and ur CO level...it should b at 1.5...
Third, fuel pump relay.This my friend, I've a spare.Mayb can test it out...
Fourth, fuel pump regulator.There's another thread here which I've explained on how 2 check this unit.
Fifth, air slide valve.It's very normal 4 this thing 2 kaput at this age.
Sixth, throttle body.Service them.

Regarding da fuel pump relay, play wif da thick red cable n see how engine behaves...most of the times,it's just loose contact.

And the gadget...I believe it's da TDC sensor.Dont worry,this unit either
works 100% fine or it fails completely!

Welcome 2 da world of wheeled sharks...fine tune dis machine n it would
put a lot of newer cars to shame :nyehehe:

Regards B)
 
Hey Wolverine wassup

Hey you da technical guru! How's your car running? Any more track sessions?
 
Originally posted by E28driver@Jun 25 2005, 04:50 PM
Hey Wolverine wassup

Hey you da technical guru! How's your car running? Any more track sessions?
Hi bro,

My baby is good...Track day? How bout dis 17th?

Regards B)
 
IF you need to find a place for wiring, my guy is quite good. He successfully rewired my e28 and upgraded the jetronic management system to a e34 motonic one thus enabling me to re-chip it with a hartge chip.

If you need to do your interior, I can recommend my upholstery guy. Using Mbtexx material, covering dash cost me RM350, re-carpetting, re-roof lining, re-upholster seat with mbtexx plus autotexx equivalent, re-doing rear speaker shelf and re-leathering the streering wheel cost me less than RM2000.... salivating.... let me know if want to see pics..

Happy shark nosing...
 
525 is a m20 engine!...e28 only has 520,525 with m20 engines...
528,535 with m30 engines....

never heard of one e28 of having a m30 2.5 engine...anyone??
 
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