Looking for a little bit of advice /tech support. I have a 93 LX Foxbody. I bought this car about a year ago and just had a complete rebuild done on this car. The engine was bored 30 over, balanced, Trickflow top end kit, new pistons, rods, and crank. So two weeks ago I put the engine back in the car all I could get the car to do was idle for about 20 seconds then it would surge out between 1 and 2,000 RPMs and die and rinse and repeat over and over. On a whim today I unplug the mass airflow sensor and the car idles like a champ at 750 RPMs I tried cleaning the MAF and cleaning the connector with electrical cleaner but whenever I reconnect it the car surges out like before. Would you guys spend the two hundred bucks on a new MAF if so what do you recommend or is there some other direction you guys would go. I would like to add that I bought this about a year ago the injectors are part #(962 280 150 945) these are 28.5 lb flow rate BOSCH injectors I'm assuming they are considered 30lb. Also, I'm assuming the MAF is calibrated to the injectors because before rebuild it ran just fine it's smoked a bit but ran fine.
Electrical 93 LX 5.0 Will not idle with MAF Plugged in
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Blown88GT
Founding Member
The MAF's are matched to the injectors; the calibration is burned into the EEC-IV ROM.
Therefore, you need to know what MAF & what injectors you have.
The Bosch P/N that Google finds is 0 280 150 945 (28.55 lb). Can't tell you what vehicle they came from.
All Fords of the era used Bosch injectors, don't assume these are 30's.
Ford Racing also used Bosch injectors, the 30's (which I still have) are red. A picture might help. This is just a sample.
If using the '93 MAF, it is not a match & will not function correctly. The factory MAF is matched to 19lb injectors.
Unplugging the MAF throws the ECU into "limp home mode"
With the rebuild, you have better combustion & air flow & the ECU is no longer able to compensate for the MAF/injector mismatch.
You could throw some used 19lb injectors in there & it should run like a champ. 19's are good for 300hp
Therefore, you need to know what MAF & what injectors you have.
The Bosch P/N that Google finds is 0 280 150 945 (28.55 lb). Can't tell you what vehicle they came from.
All Fords of the era used Bosch injectors, don't assume these are 30's.
Ford Racing also used Bosch injectors, the 30's (which I still have) are red. A picture might help. This is just a sample.
If using the '93 MAF, it is not a match & will not function correctly. The factory MAF is matched to 19lb injectors.
Unplugging the MAF throws the ECU into "limp home mode"
With the rebuild, you have better combustion & air flow & the ECU is no longer able to compensate for the MAF/injector mismatch.
You could throw some used 19lb injectors in there & it should run like a champ. 19's are good for 300hp
The MAF's are matched to the injectors; the calibration is burned into the EEC-IV ROM.
Therefore, you need to know what MAF & what injectors you have.
The Bosch P/N that Google finds is 0 280 150 945 (28.55 lb). Can't tell you what vehicle they came from.
All Fords of the era used Bosch injectors, don't assume these are 30's.
Ford Racing also used Bosch injectors, the 30's (which I still have) are red. A picture might help. This is just a sample.
If using the '93 MAF, it is not a match & will not function correctly. The factory MAF is matched to 19lb injectors.
Unplugging the MAF throws the ECU into "limp home mode"
With the rebuild, you have better combustion & air flow & the ECU is no longer able to compensate for the MAF/injector mismatch.
You could throw some used 19lb injectors in there & it should run like a champ. 19's are good for 300hp
Blown88GT
Founding Member
I am more than familiar with the C&L (Cathy & Lee Bender).
I talked with them many times. Lee was an an authority on air flow through orifices (as in rocket engines).
His flow bench was 2nd to none.
He did work for NASA Marshall Space Flight Center since both he & them were in Huntsville, AL.
Marshall is where all the US rocketry was designed, as in the Saturn V/Apollo 11.
Is it the C&L 76mm or 73mm housing?
What is the color of the C&L calibration tube?
Once you know the color, you can get injectors to match.
Let's assume the injectors are close enough to 30's to use them as 30's.
See if you can find out anything more about those injectors, maybe they aren't really 28.5's.
If they are not Ford, the fuel pressure could be something other than the Ford standard of 39.15 psi.
An adjustable FPR may be all you need to compensate. Kirban is the only one to get.
Raise the pressure to 45 psi & now you have 30's.
http://www.csgnetwork.com/fiflowcalc.html
For 73mm housing, cal tube is black
For 76mm housing, cal tube is purple
If you are still using the C&L cold air intake & MAF & air filter are located where their supposed to be, you're good.
https://shop.macperformance.com/MAC...679BBF4F82C1B7EDF384B9754C86F.p3plqscsfapp005
This was all done when a "tune" was something you hummed or played on a musical instrument.
It works well if you pay attention to MAF & air filter locations. If not, it's troublesome.
They were mainly designed for WOT using the factory EEC-IV with no chip.
I'll put this link here, it's all that left of C&L website after he sold the company to MAC Performance & retired.
https://web.archive.org/web/20150225072815/http://www.cnlperformance.com:80/MAF_info.php?section=15
I talked with them many times. Lee was an an authority on air flow through orifices (as in rocket engines).
His flow bench was 2nd to none.
He did work for NASA Marshall Space Flight Center since both he & them were in Huntsville, AL.
Marshall is where all the US rocketry was designed, as in the Saturn V/Apollo 11.
Is it the C&L 76mm or 73mm housing?
What is the color of the C&L calibration tube?
Once you know the color, you can get injectors to match.
Let's assume the injectors are close enough to 30's to use them as 30's.
See if you can find out anything more about those injectors, maybe they aren't really 28.5's.
If they are not Ford, the fuel pressure could be something other than the Ford standard of 39.15 psi.
An adjustable FPR may be all you need to compensate. Kirban is the only one to get.
Raise the pressure to 45 psi & now you have 30's.
http://www.csgnetwork.com/fiflowcalc.html
For 73mm housing, cal tube is black
For 76mm housing, cal tube is purple
If you are still using the C&L cold air intake & MAF & air filter are located where their supposed to be, you're good.
https://shop.macperformance.com/MAC...679BBF4F82C1B7EDF384B9754C86F.p3plqscsfapp005
This was all done when a "tune" was something you hummed or played on a musical instrument.
It works well if you pay attention to MAF & air filter locations. If not, it's troublesome.
They were mainly designed for WOT using the factory EEC-IV with no chip.
I'll put this link here, it's all that left of C&L website after he sold the company to MAC Performance & retired.
https://web.archive.org/web/20150225072815/http://www.cnlperformance.com:80/MAF_info.php?section=15
It's a purple tube 76MM and my fuel pressure is 42psi as I have an adjustable FPR. I have googled for an hour these injectors seems to be 28.5 that came from a Cappa Vortech Supercharger Kit https://www.bulletperformanceracing.com.au/Bosch Fuel Injectors Table 150.html.
Boostedpimp
Dirt-Old 20+Year Member
Can you find another member or local with a 30lb calibrated maf that you can just swap in to see what happens with? Maybe the maf shat the bed?
Blown88GT
Founding Member
MAF & injectors appear to be matched.
Time to perform the Surging Idle Check List.
https://www.stangnet.com/mustang-forums/threads/help-me-create-the-surging-idle-checklist.698148/
Time to perform the Surging Idle Check List.
https://www.stangnet.com/mustang-forums/threads/help-me-create-the-surging-idle-checklist.698148/
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