MyE28.com

i put a 325i intake manifold and throtle body on my 1983 528e. now it seems liek the lager intake and throtle body are causing me to run lean. what can i do to rich up the fule mixture. i adjusted the air meter and i still get lean. any ideas any one?

Sounds like you have a vacuum leak. Air bypassing the AFM that's not getting metered will cause the amount of fuel injected to be too little.

first of all, how do you know you are running lean? do you have a A/F ratio gauge?

next, when you installed the 325i throttle body, did you port the head to match? if not you have some serious turbulence right where the injectors spray.

What else did you swap when you swap the manifold? I hope the injectors you are using are correct.

We need to know some more info to diagnose correctly

i did not port the head . just slaped it on . i have an o2 meter gauge . an thats what is showing im lean. also my spark pluggs confirm this. now as for un meetered air . i dont have any vac leaks that i know of. im still getting abit more than -20 inches hg vacume during idle. unless i am suposed to have more vacume? now i have an eta head on this car. and im not quite sure about porting or milling it. is it ok to port it out so the ports match or will i hit a water jacket or something important ?

zundfoldge wrote:i did not port the head . just slaped it on . i have an o2 meter gooahj . an thats what is showing im lean. also my spark pluggs confirm this. now as for un meetered air . i dont have any vac leaks that i know of. im still getting abit more than -20 inches hg vacume during idle. unless i am suposed to have more vacume? now i have an eta head on this car. and im not quite sure about porting or milling it. is it ok to port it out so the ports match or will i hit a water jacket or something important ?

You need to pull that manifold off and look at the shape of the ports, now look at the shape of the ports on the head, see a difference? you need to put the 325i intake manifold gaskets on the head, draw the shape on the head , and get grinding. you can do this with out taking the head off, as long as you stuff many rags in the ports so no shaving fall into your engine.

I'm not sure if this will solve the lean problem, but I am sure that 325i manifold does not benefit the rest of your engine the way it currently is.

as for the lean condition, Check Fuel pressure.

fule pressure is good. the other thing i noticed it only runs lean after it warms up. and gets to full operating temp about 170 fh. im still not shure about grinding though. just want to make sure thats a must first. not to discredit you in any form.

Didn't you install a Super E or 325i head also?

Did you make sure you got all the old intake gaskets off before installing the thing? If you have some doubled up, or one missing, you will have a huge air leak and you could even blow some fuel out because the injectors are right there.

zundfoldge wrote:it only runs lean after it warms up. and gets to full operating temp about 170 fh.

check the sensors on the thermostat housing, sounds like one or all of them are bad.

The 325i intake and throttle will not cause lean running on an e motor. You'll lose power, but it wont run lean. You likely have a leak in the intake elbow, the idle control hoses or the crank breather hose. None of those affect intake manifold vacuum, but they are all air leaks. You should probably put the e intake and throttle back on. I have tried this before, and it wiped what torque the e made around 3k and gained nothing on the top end. I had much better acceleration with an e intake than an i intake on an e motor. And forget about porting the e head for the i manifold. It doesn't make a difference. I tried that too. You need to start with Motronic 1.1/3, a decked 325i head and a hot cam. You can wire an e30 harness into the e28 in a weekend if you know what you're doing and you have all the parts you need. Basic motronic sucks, and will never support any kind of power. Once you get i fuel injection in there, you can do some real motor work...

Kyle in NO wrote:Didn't you install a Super E or 325i head also?

i had one . it got wasted with the old motor.

turbodan wrote:The 325i intake and throttle will not cause lean running on an e motor. You'll lose power, but it wont run lean. You likely have a leak in the intake elbow, the idle control hoses or the crank breather hose. None of those affect intake manifold vacuum, but they are all air leaks. You should probably put the e intake and throttle back on. I have tried this before, and it wiped what torque the e made around 3k and gained nothing on the top end. I had much better acceleration with an e intake than an i intake on an e motor. And forget about porting the e head for the i manifold. It doesn't make a difference. I tried that too. You need to start with Motronic 1.1/3, a decked 325i head and a hot cam. You can wire an e30 harness into the e28 in a weekend if you know what you're doing and you have all the parts you need. Basic motronic sucks, and will never support any kind of power. Once you get i fuel injection in there, you can do some real motor work...

i have an ecu for a 325i but no harness. he he he. i also have an ecu for a 325e but i dont think thats any better than my stock one from the bit i read on it. but i will check all of what you mentioned and post back. to see if i find any thing.

///ARINUTS... wrote:

zundfoldge wrote:it only runs lean after it warms up. and gets to full operating temp about 170 fh.

check the sensors on the thermostat housing, sounds like one or all of them are bad.

can i unplugg a sensore other than my o2 to keep it rich? is there a temp sensor for the ecu to know how warm the car is?

You shouldnt rig anything to mask whatever problem youre having. You should fix the problem and go from there. You should probably put the e intake back on too...

turbodan wrote:You shouldnt rig anything to mask whatever problem youre having. You should fix the problem and go from there. You should probably put the e intake back on too...

right so if i unplugg what ever sensore is bad shouldnt it stay the same or show change then i know what one to replace? or dose any one have the testing values of the temp sensores? and i could try that way as well ? im not into rigging any thing pluss it looks rediculouse on a bmw any one know the term afro engeneering

zundfoldge wrote:

turbodan wrote:You shouldnt rig anything to mask whatever problem youre having. You should fix the problem and go from there. You should probably put the e intake back on too...

right so if i unplugg what ever sensore is bad shouldnt it stay the same or show change then i know what one to replace? or dose any one have the testing values of the temp sensores? and i could try that way as well ? im not into rigging any thing pluss it looks rediculouse on a bmw any one know the term afro engeneering

How do you know a sensor is bad? If it didn't have this problem before the work you did, it would make sense to check out what you have messed with. I bet you didnt replace your intake elbow or any other hoses during the intake swap, and one of those is probably dicked up. Perhaps you got a connector on wrong, or you left a hose off. Troubleshoot it. Have you checked your intake boot?

i checked my intake . i had to but a new rubber boot because of the size differance in the throttle bodys. so i am all good there . now i have three vac lines one for the climate control two for the fule pressure regulator. and three the brake booster. and no leaks there.

What did you do with the charcoal canister purge line? How about the crank breather hose? What did you do about the idle air control hoses? They dont fit the 325i air boot.

turbodan wrote:What did you do with the charcoal canister purge line? How about the crank breather hose? What did you do about the idle air control hoses? They dont fit the 325i air boot.

i vented the crank case to just open air. the charcole canister is gone so thats not hooked up. now the idle control hoses and cold stat injector are still plumed on the manifold just like you would see on an 528e or 325e.

i still only get the lean problem when i am at full operating temp. car is very responsive. no lagging or missing at all . vac air fule and spark all proper when cold . drives liek a champ. just for some reason i get lean under full throttle. and i have replaced my fule filter in the last four months. im stumped.

zundfoldge wrote:i vented the crank case to just open air.

I hope you plugged the other side. this could be your massive vacuum leak.

///ARINUTS... wrote:

zundfoldge wrote:i vented the crank case to just open air.

I hope you plugged the other side. this could be your massive vacuum leak.

i did away with having any vac to it. since it was gone.

other thought. the engine i put in my car is from a 1987 325es.
the 325i manifold is from a 1988. it still has the 325i throttle possition sensor on it. my car is a 1983 528e . could the diference in the years on the parts be problem?

Please get a spell checker!

wkohler wrote:Please get a spell checker!

ok ok just a sec. my key board bateries are going dead. cant find new ones yet.

zundfoldge wrote:

///ARINUTS... wrote:

zundfoldge wrote:i vented the crank case to just open air.

I hope you plugged the other side. this could be your massive vacuum leak.

i did away with having any vac to it. since it was gone.

other thought. the engine i put in my car is from a 1987 325es.
the 325i manifold is from a 1988. it still has the 325i throttle possition sensor on it. my car is a 1983 528e . could the diference in the years on the parts be problem?

But theres a large, probably 1/2" tube on the throttle body that the hose connects to. This is a massive vacuum leak if you dont have it plugged or connected. We're not talking about vacuum lines here.

#11 goes up to the bottom of the intake manifold. What did you do with that?

Skeen wrote:

#11 goes up to the bottom of the intake manifold. What did you do with that?

In this case it could only be a major oil leak. He said he vented the crank breather from the valve cover to the atmosphere. I still wonder what he did to plug the big-ass fitting the other end of it goes onto at the throttle body, but either way #11 is out of the vacuum circuit.

part #11 still goes directly into the manifold. from there it is vented to the chamber or space under the valve cover. now the valve cover has been vented to atmospher. the throttle body has been plugged off. so that theres no vac loss.

I dont know mang. There must be something wrong with it. You might just have to figure it out.

Does your valve cover have a breather hose, that connected to the intake? Is this the crankcase vent you say is vented to open air?

Pics would be very helpful.

since i got the time im gona taker er apart and see what i can find. i'll put some picks up. and let you guys pick it apart see if theres any thing i have missed