Author Topic: Runnning rich with Mustang injectors (Read 8110 times)

spanish_pants · « **on:** May 30, 2010, 06:56:17 AM »

Hey all, i recently installed the Mustang injectors i bought. Installation was pretty straight forward with no problems, but the car is now running very rich. The smell of fuel from the tail end is nauseating.
Anyone have this problem?

bmwconnect · « **Reply #1 on:** May 30, 2010, 09:01:33 AM »

what are the part numbers on the injectors?

spanish_pants · « **Reply #2 on:** May 30, 2010, 09:17:44 AM »

I don�t have the part # right now, but they are these...
http://cgi.ebay.ca/8-BOSCH-19LB-19-LB-MPI-FUEL-INJECTORS-DESIGN-III-FORD_W0QQitemZ320538652863QQcategoryZ33554QQcmdZViewItemQQ_trksidZp4340.m263QQ_trkparmsZalgo%3DDLSL%252BSI%26its%3DI%252BC%26itu%3DUCI%26otn%3D10%26pmod%3D320526415944%252B320526415944%26po%3D%26ps%3D63%26clkid%3D8171597919236596541

tjts1 · « **Reply #3 on:** May 30, 2010, 11:12:13 AM »

Were the injectors exactly the same color? Do you live in the US? If they were in fact 19# injectors, you could have a sticking or failed injector in the batch. This is why i never buy 'reconditioned' injectors that people have messed with. I would rather take used injectors straight off the JY car.
EDIT:
This can also be a symptom of a failed or disconnected FPR vacuum hose. Its kind of tricky to reconnect once you had your manifold off.

spanish_pants · « **Reply #4 on:** May 30, 2010, 11:29:44 AM »

Actually i�m living in Spain currently. Ii picked these up while i was back home in Canada on business. All the injectors in the set appeared to be the same color.
We were in a bit of a rush to get this done as it was getting late, when i have some free time tomorrow i�ll take the manifold off and look at the hoses to make sure they�re all snug.
BTW which hose is the FPR hose?

tjts1 · « **Reply #5 on:** May 30, 2010, 11:40:44 AM »

The vacuum hose from the FPR plugs into the side of the throttle body in a really stupid location. Hard to reach and easy to overlook.

cheers
Justin

spanish_pants · « **Reply #6 on:** May 30, 2010, 11:45:04 AM »

Thanks Justin! I�ll go take a look at it now. If it�s not then i�ll take the other set of 4 injectors to get tested and replace the ones i just put in.

Ok, it looks like it�s connected, so that�s not the problem. On to plan B...

tjts1 · « **Reply #7 on:** May 30, 2010, 12:00:53 PM »

UGH, thats annoying. It really shouldn't be running any different with the 19# injectors. Does the Spanish 318is have an O2 sensor and cat? If not, it really can't adjust for bigger injectors during closed loop. But again, you're using the same size injectors as stock.
EDIT:
The stock injectors are 192cc and the EV6 injectors you installed at 208cc. If your car isn't equipped with an O2 sensor, then it will be running ~7% rich compared to stock. The O2 sensor in the US market cars allows the fuel system to adapt to the slightly larger injectors during closed loop operation (light load), and then go into open loop at high load where you would want the additional fuel flow.

PumpItUp · « **Reply #8 on:** May 30, 2010, 05:19:39 PM »

i have the same injectors (155 746) off a late 90s s60 or s90, forget which
runs great. but i have a n. american car

spanish_pants · « **Reply #9 on:** May 31, 2010, 06:11:03 AM »

Quote from: tjts1;93049

UGH, thats annoying. It really shouldn't be running any different with the 19# injectors. Does the Spanish 318is have an O2 sensor and cat? If not, it really can't adjust for bigger injectors during closed loop. But again, you're using the same size injectors as stock.
EDIT:
The stock injectors are 192cc and the EV6 injectors you installed at 208cc. If your car isn't equipped with an O2 sensor, then it will be running ~7% rich compared to stock. The O2 sensor in the US market cars allows the fuel system to adapt to the slightly larger injectors during closed loop operation (light load), and then go into open loop at high load where you would want the additional fuel flow.

Thanks for the info Justin, this is something i didn't know.

I can�t speak for all Euro 318�s, but mine didn�t come with a catalytic converter or O2 sensor. I suppose in those days it wasn�t mandated for european cars.
On the plus side, the car does run smoother and responds much better under acceleration. With it running this rich it i don't think it will pass the emissions test unless there is a solution.
Is there anyway to adjust the air/fuel mixture?

DesktopDave · « **Reply #10 on:** May 31, 2010, 10:07:11 AM »

I'd think about welding an O2 sensor bung in, maybe even use a wideband sensor. They're only $200 now and you'll get a great idea of what the car is doing. It'll improve your fuel economy as well. You don't need a cat to do it. Unless you're using leaded AvGas I don't think it'll be a problem.

tjts1 · « **Reply #11 on:** May 31, 2010, 11:55:41 AM »

Quote from: spanish_pants;93077

Thanks for the info Justin, this is something i didn't know.

I can�t speak for all Euro 318�s, but mine didn�t come with a catalytic converter or O2 sensor. I suppose in those days it wasn�t mandated for european cars.
On the plus side, the car does run smoother and responds much better under acceleration. With it running this rich it i don't think it will pass the emissions test unless there is a solution.
Is there anyway to adjust the air/fuel mixture?

I think O2 sensor and cat in europe depended on what country you were in and maybe options list. The ultimate solution in this case in Megasquirt but just to get you through emissions testing, you can adjust the AFM a bit but as mentioned above, you really need to have some kind of feedback from the exhaust.
http://mysite.verizon.net/vzerdcib/e34a/id6.html

spanish_pants · « **Reply #12 on:** June 01, 2010, 08:45:42 AM »

I have until November until i have to pass my yearly inspection so i have some time to deal with this, but it looks like i�m going to have to put in the O2 sensor.
How difficult is it to weld the O2 bung in? I assume that after install the sensor in the car shouldn�t run as rich.

BTW, thanks everyone. This should help out all the other euro owners who want to run the mustang injectors as well.

tjts1 · « **Reply #13 on:** June 01, 2010, 10:12:31 AM »

I don't know if you can just add an O2 sensor to the car. You would also need the ECU and wiring harness from a car that had an O2 sensor. Time to bust out the wiring diagrams.
http://www.autolib.diakom.ru/CAR/BMW/1991/318%20Series/WIRING%20DIAGRAMS/fig02.pdf

flyinglizard · « **Reply #14 on:** June 01, 2010, 10:20:25 PM »

Try changing the air door position. Add about 3-5 clicks of tension to the coil spring.
Maybe you could lean it with the airtemp sensor or HOH temp sensor. It would need to read about 20% hotter than real.
I would do the air meter thing first, followed by the air temp sender( In the AF meter), than the water temp sender,as it is under the intake. Look in t he book to see how much resistance value to change .
Ps I foregot, there is a air bypass screw under the plug on the AF meter. Maybe you can get some leaner by opening that up. You have to pull out the plug, ( soft lead). back out the allen screw. This only affects the very low end of rpm. MM