Lack of power

[Mark Babb 1]

Hi All,

Hopefully someone might be able to shed some light on a problem after collecting race car last week.

1990 E30 320 110,000km.

after driving the car for the first time this weekend, it has a misfire around 3,000rpm and then clears further up the revs, however it has a distinct lack of low down power. Took Car to Jerry Clayton (only people open this week), checked timing all ok.

They have suggested it could be many things faulty ECU, EMS, Crank sensor, and so on.

The car was a one lady owner low milage that drove perfectly before spending 3 months in race car preperation.(Auto to Manual conversion aswell)

Was talked into purchasing a recon head complete from European Auto, although i had no problem with existing head. (it was suggested to me that 320's have a problem with heads and when they showed me a nice freshly recon head that they have done next door seemed liked a sensible thing to do)

Options i see at present...swap heads back, but cannot see why a different head would make the difference.

Replace ECU, EMS and everything else BMW have suggested, but this would cost a fortune new, and bit concerned second hand may also have a fault.

So sitting here pulling out my hair and now wondering if i will be able to get the car fixed for the meeting end of January.

Just wondered if anybody else has experienced anything similar and may be able to pass on some advice.

Thanks

Mark

[gmccormack 0]

Have you checked to see if the AFM flap is moving freely??

[drifty325i 0]

All the spark plug leads 100% ? could be as simple as that.

[ducatiss 1]

I would agree with the comment re the AFM. it would be worth checking. Try a second hand one - they aren't that expensive. The usual thing is to replace all the usual ignition components first - plug leads (though the originals don't usually give too many issues on the E30) Check to see that a lead isn't broken and arching on metal somewhere. Are all the plugs the same colour? Also check your valve clearances. You could also try borrowing an ECU to see if that solves your problem. The 320 heads don't give as many problems as the 325 as a rule - the 325i head having a distinct lack of metal in some critical places around the water galleries. If your old head was in good condition and all clearances correctly set then that wont be the problem.

My advice - start on the ignition/electrical side first then work from there.

Edited December 29, 2006 by ducatiss

[Mark Babb 1]

Thank you for all the advice.

Will check as mentioned and keep you posted.

Mark

[10hove 0]

Thank you for all the advice.

Will check as mentioned and keep you posted.

Mark

First off they do have a distinct lack of power under 4,000 rpm, but I wouldnt worry about that too much as on the track your seldom down that low.

The best thing to do is to get it tuned properly on the dyno by someone who knows what they are

doing, to get the mixture right across the range.

In hamilton we use tuning and performance, in Auckland I understand Bob Homewood is pretty good

It will probabaly be the best $500 or so you will spend on your car, provided everthing else is up to scratch

You might even find some guys willing to share comparative horespower figures

Cheers

hove

Edited December 29, 2006 by Alex ten Hove

[will 169]

Reading your problem of a misfire, I wondered if it wasn't my favourite plug giving you problems.. below is from a post I made some time ago. Check it out, it controls a host of things on the engine which could contribute to your problem.

Apart from this, check the resistance across your HT leads, check dist cap for crack, rotor for leakage to earth and even possibly condensation under the dist cap..

Maybe your injectors need a cleaner through them after standing idle for a while.

Check all earthing points for the engine loom etc, earthing can be a major source of frustration in the e30.

I don't suppose you replaced the cambelt while you were at it?? It is bloody easy to get it 1 tooth out... That would cause a lack of power. If you havn't, I would do it as a matter of course as you will be thrashing it around the track and you dont want it to break at 7000rpm, believe me!!!

I have attached another pic of the plug in question as I can't get the photo across from the other posting..

Will

Just thought I would bring up the subject of fuel line maintenance and offer possible solutions to other problems I have seen some of you having recently.

I have just acquired a F/L E30 325 and it was having some problems with starting, idle being erratic and temp gauge playing around, so I went looking for the cause.

I had had this particular problem with a previous F/L, and had solved it after much hair pulling, so I immediately looked for the bast*rd plug which sits under the inlet manifold just in front of the starter. (Only some later F/L cars have it.) Found the bast*rd and tried to open it to clean the terminals and see if it had water in it. Got it apart eventually and discovered that all the terminals were badly corroded and, in the process of cleaning, a wire broke off, it was so badly corroded. I decided to remove the plug completely and replace it with these crimp male/female electrical terminals. Did this, used some heatshrink on each wire to waterproof it and taped it all up.

In the process of doing this, I had to remove the airbox, so the fuel lines were then obvious. I immediately noticed that a T piece in the fuel line had no clamps on it!!! After some members' recent car fires, this was just a fire waiting to happen.

I pulled this main fuel line to the pressure regulator off to put a hose clamp on, and noticed that what had appeared to be a perfectly good fuel line, had signs of fine cracks on it. I then totally removed it to more closely examine it and found it was in fact just about to split open.... bending it sharply produced some scary big cracks, and in the process of trying to photograph it, one split right through. So what had appeared to be good at first glance, was in fact ready to pack in, and probably ignite the car in the process. I then examined all the other fuel lines and found them ok.

I replaced this line, reassembled the airbox and started the car. No more hard starting, idle good and temp gauge steady. No slight misfire anymore on hard acceleration. (I had put this down to spark plugs probably past their use by date).

This is the second time I have had problems with this plug, so would suggest that those of you who have F/L cars, check it out closely especially if you are experiencing the problems I described above.

I have attached a photo showing the guilty plug (now removed) and the fuel line showing the deep cracking that wasn't obvious on first glance.

Just really posted this in the chance it might be of help to some of you with starting/idle problems, and encourage you to check your fuel lines for possible disasters.

Good luck... (sorry for the essay..)

[Mark Babb 1]

Thanks Will/Hove and others.

Your assistance is really appreciated.

The car started off in excellent order, low km's, Lady owner etc etc. Paid top money for the car as i wanted to start with a good foundation.

Whilst they were building the car i obtained new Cam belt, plugs, dist cap etc and had these fitted whilst engine was out of vehicle.

Car currently with Jerry Clayton BMW who confirmed yesterday that the timing was correct. They will check valve gaps on weds when they reopen. First question they asked was the replacement head from a 325? European Auto's certainly supplied it to me as a fully recond head for FL 320, so no reason to think differently.

Whilst engine was out the race builders did steam clean engine so i suppose water could have got in somewhere, but then again plugs, dist cap have all been replaced.

Will check HT Leads, and rotor on weds and go hunting for this plug under manifold.

One other question concerning this recon head i was sold...are the heads different from FL 320 to earlier models, could compression difference be a cause of erratic idle, misfire midrange and lack of bottom end power?

Hove, would you have a contact number for Bob Homewood in Auckland as i have not heard of him. It would be a great help to find someone local in Auckland (north shore) that i can use to assist me with the car. Nothing against Jerry Clayton's but i'm dreading the invoice.

Thanks Again

Mark

[Carl 3]

Your head casting should have a 731 on it, if it doesn't it's the pre-fl. You should do a quick ECU swap from another race car to rule that out. Lack of power sounds normal for the 320 but misfires aren't.

[10hove 0]

Your head casting should have a 731 on it, if it doesn't it's the pre-fl. You should do a quick ECU swap from another race car to rule that out. Lack of power sounds normal for the 320 but misfires aren't.

bob homewood is in Puke near then track details below, just a note that at the kmns your car has done the airflow meter should probabaly either be repaired or replace as they wear out,

Bob Homewood Motorsport

Phone: (09) 238-8754

Fax: (09) 2388754

Street Address

8 Crosbie Road

Pukekohe

Auckland South

Postal Address

8 Crosbie Road

Pukekohe

Auckland South

regrds

Hove

[conrod 1]

Mark,

cylinder head not likely to be the source of problem, unless it is cracked and water in going into combustion chamber, and you would probably notice it using water if it was.

Give Gavin Bellars a call regarding Dyno tuning, he is on the shore, has a good dyno,and knows BMW's inside out.He has run several of the E30 cars already, so has a good database to compare yours to. Furthermore he is much more friendly when it comes to invoicing than Jerry Claytons, if you get my drift!

Hi Velocity Ltd

16D Parity Place

Glenfield

021 483 562

442 4451

cheers Conrad

Edited December 30, 2006 by conrod

[hybrid 1039]

Car currently with Jerry Clayton BMW . . . . .

Yours was the grey e30 in at glenfield jerrys ? I was the guy when you were talking to keith who asked if it was a race series car. I had another look at your car later in the day when I went back to get the m3 struts hub nut put on, and all I can say it im very impressed with it ... it must be one of the cleanest interiors i've ever seen in an e30 race car!

[Mark Babb 1]

Yours was the grey e30 in at glenfield jerrys ? I was the guy when you were talking to keith who asked if it was a race series car. I had another look at your car later in the day when I went back to get the m3 struts hub nut put on, and all I can say it im very impressed with it ... it must be one of the cleanest interiors i've ever seen in an e30 race car!

Thank you for the kind comments.

The car was prepared by Race FX in Henderson. It only went into for a roll cage....$20,000 later....Mind you everything underneath the car is just as clean as i had every component detailed before reassembly. Just a little frustrating that it went in with a smooth running engine and has come away with this problem. Hopefully the guys at Jerry Clayton will find the problem on weds otherwise it will take it to Hi Velocity just up the road later in the day. I am sure with all the kind assistance offered by everyone on this forum i will find the problem

Thanks Mark

[kiwi535 538]

your symptoms sound exactly like fmy M30 bfore it got a new dizzie cap....Tke of the new one make sure all is clean and dry inside......maybe the sitting around has caused some condensation....

[Mark Babb 1]

Thanks Conrad for the contact.

Gavin Bellars found the problem within 30 mins (Jerry Claytons had the car for 2 days and still could not find the fault)

Faulty ignition coil and one spark plug cap corroded.

Thank you everyone for advise given.

Mark

[nz320i 0]

hmmm thats why i dont like dealerships when you have problems, there love to replace numerous parts till the problem goes away rather than find it. Had that before..