Juddering when accelerator slightly in use....

[smithy318i]

Dunno if it's applicable to a 318i, but there was a good diagram on a Russian site in this thread:
http://www.e30zone.net/modules.php?name ... highlight=

.

I know about that one. I supplied it.

[Speedtouch]

Oh OK, useful diagram dude

[daimlerman]

320iSE,Yes I let engine idle for a while,but I am running on the loan ECU at the moment.When my suntanned one finds its way home I will let you know if there is any further improvment.So far engine seems to breathe more freely and fuel consumption has improved a little and my only issue is this hiccup at 1000rpm off throttle slowing down.I expected Miller to supply a custom chip to suit my motor,NOT that they would want to write their MAF instructions onto my 2.7 zone chip.I was hoping to have a s/hand chip to sell on to help ofset the cost of the MAF!! I would ask that if anyone else requires a 2.7 chip in the future that they buy from Ant/zone shop,rather than buying from the USA...

[Speedtouch]

Suntanned...in Canada? Miller sent me a 7,000rpm chip last week (free of charge! ) and it seems a little smoother than their standard 6,500 rpm one (although I was particularly careful about installing it and letting it idle for the requisite 10 mins at least, and switching off prior to using it).

Good to hear you're noticing some benefits already: it'll be interesting to hear your experience with your original ECU in place. If anything, i'd have thought the Yanks/Canadians would have better chips for the 2.7 engines, because they have more of them over there (etas, etc.) wheras they're a relative rarity over here.

[DaveD]

I have presumed (being a cynic) , that I would have to have the new miller chip rolling road remapped to suit the current and any further alterations I might do...I have asked brody if this is posible, but the car is not on the road til april 1 so i have plenty of time

[abelai]

Is there any more progress on this problem? As it seems to be a problem for lots of people including me.

[daimlerman]

Just noticed a post by Ant about FRR.Seems that they are different settings for 320 and 325.This may well account for my improvment on swapping myFPR.GSF list three for E30.,depending upon engine.

[smithy318i]

Is there any more progress on this problem? As it seems to be a problem for lots of people including me.

Well mine seems to be solved

By bending the metal bit inside the AFM so that it runs across a different piece of the PCB.



I also sprayed carb cleaner into the rocker cover vent hose while the engine was running, and held the engine revs up to prevent it from stalling.

Despite what Brian said about the AFM not being used by the ECU at idle, mine responded to adjutment while at idle.

The idle is back up to 900 and the hunting has also gone away. Lets hope it stays that way.

[abelai]

I have finally solved my lumpy running kangaroo issue i restricted the fuel return from the fuel pressure reg therefore increasing the fuel pressure and it runs much smoother. The increased fuel pressure is forcing the injectors to close fully rather than costantly dribble one application of cataclean later and the car runs fine. This might be the same problem as other people and almost definately if you are running an lpg conversion and have no problems when running on gas.

[daimlerman]

What sort of snake oil is cataclean,please?

[abelai]

It's an injector cleaner that also cleans lambda sensors and cats seems good stuff probably no different to any other injector cleaner though but worked for me.

[Speedtouch]

Abelai wrote:

I have finally solved my lumpy running kangaroo issue i restricted the fuel return from the fuel pressure reg therefore increasing the fuel pressure and it runs much smoother.

What did you do to restrict the fuel return?

Cheers,

[abelai]

Just piniched the fuel return off the FPR this forces the fuel pressure to rise giving more pressure to the back of the injector forcing the pin to close tighter.

Cataclear or Cataclean is available from GSF.

[abelai]

I have just recieved my Miller MAF also, so will be fitting that shortly and let people know how it goes.

[daimlerman]

abelai,Thanks for the info,I will pick some up and try it.I am down to one hiccup as I pass through 1000rpm now.To summerise my work so far;1,replace inlet manifold nuts with new,self locking ones.2,careful sealing of all inlet pipework and connections(small improvement)3,Miller MAF,improved running and economy.4,swapped 2.5 bar FPR for 3.0 bar FPR(large improvment)I am checking fuel consumption again,last tank gave 25.6mpg,current indications are that the current tankfull will be around 30mpg.,but I have swapped the diff for a 3.64 as well....

[Speedtouch]

Good stuff. I can quite easily get 30mpg with my Miller MAF

Abelai, what did you use to pinch the hose, some sort of adjustable clamp? It's certainly an interesting idea to try! (Not that mine judders often now i've gone for the MAF conversion, though it has done it once or twice, after a cold start.)

Cheers,

[Chuffy]

Hi there folks, I'm new here so go gently

I get this is my newly acquired 1985 316 (no fuel injection). It just doesn't like running at 30mph without kangarooing a bit. Apart from that it runs fine (it's only done 52,000 from new!!).

One thing I have noticed is that there are two temp senders on the engine next to each other and one isn't connected. The temp guage in the car works fine so what is the other one for and could that be causing any problems?

I have had a look in the Haynes Service and Repair Manual but it doesn't even mention the temp senders.

[march109]

the brown one if for the ECU I think, the blue one the temp gauge on your instrament cluster.

it should deffo be connected!

[abelai]

Hi 320ise, just pinched it with my hand as my running issue was bad at idle up to 3500rpm i suppose you could use brake pipe clamps but be carefull not to close it completely as that would stop the injectors opening as the pressure would be to high for the injector to force open. I would not advise you drive the car with the fuel return pinched.

[Brianmoooore]

Hi there folks, I'm new here so go gently

I get this is my newly acquired 1985 316 (no fuel injection). It just doesn't like running at 30mph without kangarooing a bit. Apart from that it runs fine (it's only done 52,000 from new!!).

One thing I have noticed is that there are two temp senders on the engine next to each other and one isn't connected. The temp guage in the car works fine so what is the other one for and could that be causing any problems?

I have had a look in the Haynes Service and Repair Manual but it doesn't even mention the temp senders.

There is no way your car should run at all happily once warmed up with the engine temp sensor disconnected. It should run extremely rich, should soot up the plugs and have horrendous fuel consumption, as well as run extremely lumpy.

[Chuffy]

Excuse my ignorance, my other car is a Ford Focus , but has the bog standard 316 from '85 actually got an ECU? If so, there may have been problems with it and that's why it was disconnected.

It seems to run fine when hot. It was running very rich when I got it because there was a split in the rubber gasket the carb sits on and it was sucking in air. My local garage fixed that and tweaked the carb a bit and got the emissions down to where they should be.

Having said that there is what looks to be a connector for the sensor lead to connect to?

Where can I get a lead from if in fact I do need one?

[Morat]

the brown one if for the ECU I think, the blue one the temp gauge on your instrament cluster.

it should deffo be connected!

I'm pretty sure its the other way round mate. I'm no expert tho, best if Mr Moore confirms?

[Ricksta]

SPot on Morat! I changed the brown one first believing it to be the one which sent info to the ECU only to find it gave temp display for Dashboard!
Blue sensor is the one to change (if faulty) to give correct temp readings to your ECU for cold start etc

[march109]

the brown one if for the ECU I think, the blue one the temp gauge on your instrament cluster.

it should deffo be connected!

I'm pretty sure its the other way round mate. I'm no expert tho, best if Mr Moore confirms?

I said "I think" would have expected Mr Moore to have noticed I'd co*ked up in his post !!

But what confuses me is car is still running and temp gauge is working yet one sensor is unplugged???

[Brianmoooore]

Hi there folks, I'm new here so go gently

I get this is my newly acquired 1985 316 (no fuel injection). It just doesn't like running at 30mph without kangarooing a bit. Apart from that it runs fine (it's only done 52,000 from new!!).

One thing I have noticed is that there are two temp senders on the engine next to each other and one isn't connected. The temp guage in the car works fine so what is the other one for and could that be causing any problems?

I have had a look in the Haynes Service and Repair Manual but it doesn't even mention the temp senders.

There is no way your car should run at all happily once warmed up with the engine temp sensor disconnected. It should run extremely rich, should soot up the plugs and have horrendous fuel consumption, as well as run extremely lumpy.

Ignore my reply to this totally!! Didn't notice it was a different car, and an old carb one at that!
This car won't even have an ECU for a blue temp sensor to be connected to!
My very first E30 was one of these, but I don't remember much about its workings, other than the Pierburg carb was just about a lost cause.
It had a cold start choke arrangement that I think didn't even involve any electronics at all, and an electronically controlled idle, for which there must have been some kind of primitive ECU.
It also had a coolant temp controlled valve which prevented the throttle butterfly of the second barrel of the carb from opening until the engine was hot.

[Brianmoooore]

the brown one if for the ECU I think, the blue one the temp gauge on your instrament cluster.

it should deffo be connected!

I'm pretty sure its the other way round mate. I'm no expert tho, best if Mr Moore confirms?

As you can see from my last post above, I don't always have time to read these posts properly!
The blue two pin sensor is for the ECU, and the brown single pin sensor controls the gauge.

[Chuffy]

Thanks Brian.
Maybe I should have mentioned it had a manual choke, that might have made things clearer.
There is definitely a connector for that sender to connect to, I just need the appropriate lead to see if it makes any difference. It has been to two garages (one of them a BMW specialist) and neither made issue with it so maybe it's not important.

I'll let you know if I get it connected up.

Cheers
Rob

[Brianmoooore]

If you have a manual choke control, then I think you'll find that the original BMW (pierburg) carb has been ditched, and an aftermarket (probably Webber) carb fitted in its place.
Because of this, there should be several unused sensors and bits of wiring around.

[Chuffy]

ah, that may explain it all then,

Cheers again.

[daimlerman]

My ECU arrived back from its holiday at Millers at the end of last week.I cannot tell what they have done to it just by looking,except that it has grown Miller stickers!Refitted it on Saturday and let the engine idle for 10-12mins as suggested by 320iSE.Went for a short test and the only issue was an erratic idle.Used the car for work Sunday night and the idle now seems to have settled.No judders or jerks,it is just possible to force a very slight judder by holding top and slowing down below idle with the brakes,but that is all.Er indoors used it for work and a supermarket trip last night and reported that she used top gear for the first time(??)and no I can not have it back!! I think that as is my usual case,I have found the expensive fix but the quality will be remembered long after the price is forgotten..I hope..so people,try all the cheap ideas first,then take a deep breath and fit a Miller MAF.

[liam012]

mmmmm

i dont think replacing a AFM with a MAF qualifies as a fix as such does it?

more of a case of "buying the problem out"!!

its not the best solution to the problem, mine is gone and i have replaced FPR.

though i think my dose of this complaint was exacerbated by my tall diff,

seems like its gonna be different for everyone?

who fixed this and what with?

daimlerman=MAF
liam012=FPR
320ise=MAF

who else? nice to get an idea of who got it sorted and by whgat means...

[smithy318i]

daimlerman=MAF
liam012=FPR
320ise=MAF
Smithy=AFM & FPR

[Jonny_71]

mmmmm

who fixed this and what with?

daimlerman=MAF
liam012=FPR
320ise=MAF

who else? nice to get an idea of who got it sorted and by whgat means...

Mine initially was cured by replacing the FPR, although the problem returned with a vengeance after a few weeks of smoooooth motoring. The car then decided it didn't want to rev or idle also, fitted a second hand TPS and it solved everything for £10!! Engine now runs the best it has for a long time.

Jonny

[daimlerman]

In my defence I did try all the cheap fixes first,including swapping the FPR.The AFM seems to be a weak link in the system,I would expect that a new replacement from GSF is listed at £160,so the extra cost of the MAF for the performance boost is probably worthwhile.I am certainly getting more miles to the gallon.

[Dr Firefly]

Right, thought I'd resurrect this one. People still suffering from this problem? Was maybe hoping that someone could come up with a preliminary guide of what to go through to sort this?

As far as I can see:

Vacuum intake system:
Check no hole in the rubber intake boot
Use a multi-meter to check the AFM and ICV
Check the TPS is set right
Check the throttle body butterfly's set up right?
Get a garage to check the CO?
Change throttle body gasket

Other electrical stuff?
Check the blue temp sensor

Mechanically
Check engine, diff, gearbox mounts
Check subframe bushes
Check binding on rear brakes
Check propshaft coupling, slack in diff, CV joints

Fuel system:
Change fuel filter
Check fuel pressure regulator
Run injector cleaning fluid through

Is that the beginnings of a comprehensive list to sort this problem? Any help would be appreciated, as I'm not that knowledgeable, but this is a problem that's plagued me for a year now, though replacing the rear sub-frame bushes and rear shocks has substantially damped it down, but the underlying problem is still there. If other people take that list and improve, correct, and expand on it I'd really appreciate it and I think it would be useful to other people. I've done about half the things on there, but the other half I've not gotten around to yet! How are you getting on with this problem Brian?