| igbastian |
Posted
Wednesday, May 9th 6:18pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 1
Toronto, on
'79 323i, '87 MB 190D |
Hi guys,
I've recently had the m20 installed into my 1979 323i. The car starts and runs but hesitates when accelerating. The car is only driveable by very slowly accelerating. I thought originally it was because there was no oxy sensor, but the installation of this only cured a cold start problem.
I have read about cutting out the fuel pressure regulator that is next to the fuel pump? Would this cause these problems?
my setup:
-1991 325i m20 with motronic 1.3
-4 cyl tran
-clutch and flywheel from original car |
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| JJG323 |
Posted
Thursday, May 10th 1:54am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1323
Reading MA USA
1979 BMW 323i |
You need that part to pressurize the system.
Did you clean the injectors when you swapped them in? They could be the problem on acceleration. |
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| imaradiostar |
Posted
Thursday, May 10th 6:31pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1046
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
The motronic 1.3 management can give you a trouble code readout by flashing the check engine light. Grab a manual for the car that donated the engine and wire up a "Check engine light" (since you probably don't have one in your cluster.) You can count the flashes to see if there is anything that the ECU thinks is plainly wrong.
The thing next to the fuel pump is an accumulator. Don't remove it- it helps prevent vapor lock and hot starting problems when it's working properly. You should check to make sure the fuel filter isn't partially clogged and that there is sufficient fuel flow to support full throttle operation. Once again, refer to the manual for the car that donated the engine.
jamie |
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| Greg323i |
Posted
Friday, May 11th 4:19am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 342
Melbourne, Australia
1982 Hennaröt 323i |
I'm pretty ignorant when it comes to EFI, but is there a possibility that the K-Jet fuel pump is putting out too much pressure for the EFI? Just a thought from an ignorant sumbeach. |
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| imaradiostar |
Posted
Friday, May 11th 5:21am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1047
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
My boss has an E21 315 with 323i CIS pumps/filters/etc and a late E30 engine and management and it runs perfectly- look in the car registry for a white 315/2.5i owned by "BMWWill". Assuming the send and return lines are flowing freely the regulator should take care of any excess pressure- fuel pressure should be around 37-38 PSI. It would be pretty easy to hook a guage up in the pressure side and check it.
It sounds to me almost as if there is a large vacuum leak- the valve cover gasket, all the hoses, intake manifold gaskets, oil return tube o-rings and a number of little vacuum lines and hoses can all leak. BMW engines tend to be very sensitive to leaks in any of these areas. BMW uses the intake vacuum to help keep the piston rings sealed and oil consumption down- so it's not a bad idea to check for leaks even if it wasn't the source of your problem.
jamie |
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| igbastian |
Posted
Friday, May 11th 8:03pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 1
Toronto, on
'79 323i, '87 MB 190D |
guys,
thanks for all the replies. i'm pretty sure it is the AFM- i found that I'm using one from an eta motor. when the AFM is unplugged the car runs much better! so i'm looking for the correct one now. |
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| aussie323i |
Posted
Sunday, May 13th 3:54am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 569
australia
1979 323i |
it's good you found the problem!
On the fuel accumulator front- I removed mine when I switched over to L-Jet injection because the e28/ e30 never had this part... I have not had any problems.
so I guess it's up to you whether you leave it in there or not.
good luck |
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| igbastian |
Posted
Wednesday, May 23rd 9:42pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 1
Toronto, on
'79 323i, '87 MB 190D |
engine runs like a top now with the correct AFM- then the clutch master went! fixed that and now i just have to figure out why the tachometer isn't working.
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| Scott72 |
Posted
Thursday, May 24th 8:53pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 1
Darien, CT
1982 320/6 2.7L |
Hi,
New here and am in the process of coverting my euro 320/6 from a carburated motor (2.7 eta motor - with 2.0 carb) to a 1990 M20 with motronic. My question along the lines of this thread is fuel pump related. Someone has already converted the car to an electric fuel pump (no boss for pump on the eta motor) that is mounted in the engine compartment. If I replace this with a Walbro or MSD pump etc for more pressure (the one in there looks pretty sad), do you think this will be in issue with my conversion. I do have the return lines back to the tank, so it would be a looped system like the E30.
Thanks |
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| bmw_m_320i |
Posted
Friday, May 25th 3:16am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 770
Helena, Montana
none right now :( |
if you're going from carb to EFI you'll need a high pressure pump made for EFI a carb runs at about 5.5 psi and a EFI system runs around 45psi |
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