Need Help Lack of Power

Angron2169 · 08-02-2008, 10:35 PM

OK I have a 89 Mustang LX 5.0 Worked over to a 306 b-303 cam I have 24lbs and a 75mm Mass Air calibrated for the 24lbs. A Walbro 255 Fuel Pump a new fuel filter and the timing is great ............ My problem is after all of that at full throttle it just bogs out ............. HELP PLEASE

Thanks
Allan

BigJnSA · 08-02-2008, 10:50 PM

you still have your cats?

whitey92lx · 08-03-2008, 01:37 AM

are you using any tuning software?

Angron2169 · 08-03-2008, 09:44 AM

yes on the cats ............ no on the tuning software

Thanks
Allan

Angron2169 · 08-03-2008, 09:49 AM

Could the o2 sensors not being plugged in cause this because the previous owner never plugged them in

Thanks
Allan

Mystic SVT · 08-03-2008, 02:54 PM

Check your mass air flow. My 91 was doing the same thing, I swapped it out for another one that I had off of another 91 and problem fixed...

BigJnSA · 08-03-2008, 03:27 PM

Quote:

Originally Posted by Angron2169

yes on the cats ............ no on the tuning software

Thanks
Allan

you may have a clogged cat. that will choke it.

whitey92lx · 08-03-2008, 03:45 PM

Quote:

Originally Posted by Angron2169

yes on the cats ............ no on the tuning software

Thanks
Allan

Youre the guy I met this past Friday night out at the 2920 meet!

coupe5oh · 08-03-2008, 06:03 PM

yea, need to scan for codes, make sure tuneup items, fuel filter, ignition coil/wire etc..are in good shape.

Angron2169 · 08-03-2008, 11:48 PM

yeah it is me from the 2920 meet trying to get this problem fixed it is killing me ........ all tune up stuff has been done and replaced

Thanks
Allan

whitey92lx · 08-04-2008, 12:00 AM

yeah, either the cats are clogged up, or you need a good tune..

BigJnSA · 08-04-2008, 12:06 AM

time for an o/r h-pipe!

XavB · 08-04-2008, 07:45 PM

i've heard not having the o2's plugged in can hurt your power also. does the car smell really rich? you would probably only want to run the o2's not plugged in if you got a tune for it and even then i've heard mixed answers on whether you want a tune for no
o2s's. plug those things back in as a start, that would be the easiest, cheapest thing to start with.

whitey92lx · 08-04-2008, 09:08 PM

Quote:

Originally Posted by Angron2169

Could the o2 sensors not being plugged in cause this because the previous owner never plugged them in

Thanks
Allan

I didnt even see this post! Dude, if you dont have your o2 sensors plugged in, your car will RUN LIKE SHIT!
Please get under your car and plug them back in Immediately!

**Sonic Blue 85** · 08-05-2008, 10:13 AM

If the O2 sensors are not plugged in it will run rich, if you have other things also causing it to go rich, it could be way too rich. But if the only problem was the O2s being disconnected, it should not cause the car to have a lack of power. Some people don't use them at all, the O2s are only used by the computer when it is in closed loop, so at WOT they are ignored. The MAF could easily be a problem, or could need to be tuned, I have found many Pro M meters that were way out of calibration, to the point they would hardly run, if at all. Do you have an adjustable fuel pressure regulator and if so what pressure is it adjusted to with the vacuum line disconnected?

coupe5oh · 08-05-2008, 01:47 PM

A guy came in to my work for with a cobra kit car, it had an efi 5.0 in it, It would barely stay started, i looked underneath and it had no 02's in it either, I told him, i didnt know how it was running as good as it was.

95 GTS · 08-05-2008, 09:32 PM

75mm are prone to be pieces of crap out of no where.

First, make sure the meter is clucked where the electronics are on the outside of the curve of the coldair.

second, throw it away or sell it and buy a pro M 80 and put that puppy in the fender well.

It could be as simple as someone left the spout connector out when they set timing. Do you have a regulator on that bad boy to control that 255 walbro?

fiveohfox · 08-05-2008, 10:58 PM

Have you done a compression check lately?

Angron2169 · 08-08-2008, 08:10 PM

ok comopression is good fuel pressure is good cats are not clogged we are starting to lean towards the pmas mass air sensor it is calibrated for the injectors just a thought

Thanks
Allan

XavB · 08-08-2008, 09:59 PM

did you pull the codes? or hook up the O2's?

08-02-2008, 10:35 PM	#1
Angron2169 Registered User Join Date: Jan 2007 Location: Houston Posts: 140 Trader Rating: (0)	Need Help Lack of Power OK I have a 89 Mustang LX 5.0 Worked over to a 306 b-303 cam I have 24lbs and a 75mm Mass Air calibrated for the 24lbs. A Walbro 255 Fuel Pump a new fuel filter and the timing is great ............ My problem is after all of that at full throttle it just bogs out ............. HELP PLEASE Thanks Allan __________________ 93 Mustang Cobra Clone- Sold 86 Mustang SVO- Sold 90 Mustang LX 2.3T- Sold 89 Mustang LX- Traded 64 Mustang 351W- Dynod 473hp

08-03-2008, 01:37 AM	#3
whitey92lx Registered User Join Date: Jul 2008 Location: hockley Posts: 31 Trader Rating: (0)	are you using any tuning software? __________________ http://westsidemustangs.com

08-03-2008, 09:44 AM	#4
Angron2169 Registered User Join Date: Jan 2007 Location: Houston Posts: 140 Trader Rating: (0)	yes on the cats ............ no on the tuning software Thanks Allan __________________ 93 Mustang Cobra Clone- Sold 86 Mustang SVO- Sold 90 Mustang LX 2.3T- Sold 89 Mustang LX- Traded 64 Mustang 351W- Dynod 473hp

08-03-2008, 09:49 AM	#5
Angron2169 Registered User Join Date: Jan 2007 Location: Houston Posts: 140 Trader Rating: (0)	Could the o2 sensors not being plugged in cause this because the previous owner never plugged them in Thanks Allan __________________ 93 Mustang Cobra Clone- Sold 86 Mustang SVO- Sold 90 Mustang LX 2.3T- Sold 89 Mustang LX- Traded 64 Mustang 351W- Dynod 473hp

08-03-2008, 06:03 PM	#9
coupe5oh Brewmeister Join Date: Nov 2004 Location: n.e. Sanantonio Posts: 420 Trader Rating: (0)	yea, need to scan for codes, make sure tuneup items, fuel filter, ignition coil/wire etc..are in good shape. __________________ retired 1990 Tx dps :T-5, stock bottom 302, shorty headers,o-r x-pipe, ported explorer true gt 40 heads, matching intake. E-cam 1.7's, pro-m 77, 24lb injectors, 3.90 gears. good for mid 12's on stickies.

08-03-2008, 02:54 PM	#6
Mystic SVT Registered User Join Date: Apr 2008 Location: San Marcos Posts: 93 Trader Rating: (1)	Check your mass air flow. My 91 was doing the same thing, I swapped it out for another one that I had off of another 91 and problem fixed...

08-03-2008, 11:48 PM	#10
Angron2169 Registered User Join Date: Jan 2007 Location: Houston Posts: 140 Trader Rating: (0)	yeah it is me from the 2920 meet trying to get this problem fixed it is killing me ........ all tune up stuff has been done and replaced Thanks Allan __________________ 93 Mustang Cobra Clone- Sold 86 Mustang SVO- Sold 90 Mustang LX 2.3T- Sold 89 Mustang LX- Traded 64 Mustang 351W- Dynod 473hp

08-04-2008, 12:00 AM	#11
whitey92lx Registered User Join Date: Jul 2008 Location: hockley Posts: 31 Trader Rating: (0)	yeah, either the cats are clogged up, or you need a good tune.. __________________ http://westsidemustangs.com

08-04-2008, 07:45 PM	#13
XavB Registered User Join Date: Sep 2003 Posts: 194 Trader Rating: (0)	i've heard not having the o2's plugged in can hurt your power also. does the car smell really rich? you would probably only want to run the o2's not plugged in if you got a tune for it and even then i've heard mixed answers on whether you want a tune for no o2s's. plug those things back in as a start, that would be the easiest, cheapest thing to start with. __________________ 1992 LX 5.0 - Twisted Wedge heads, Trickflow Stage 1 cam, Trickflow Streetburner Intake, Trickflow 1.6rr's, BBK shorty headers & o/r h-pipe, flowmaster catback, FRPP 4.10s, FRPP 24lb injectors, Granatelli MAF, BBK CAI, BBK 65mm throttle body, BBK FPR, Maximum Motorsports LCA's, CC plates, and strut tower brace, LMM full length SFC's, Mach 1 springs, and Bilstein shocks and struts Last edited by XavB; 08-04-2008 at 07:49 PM.

08-05-2008, 10:13 AM	#15
Sonic Blue 85 LSS Sponsor Join Date: Dec 2007 Location: New Braunfels Posts: 393 Trader Rating: (1)	If the O2 sensors are not plugged in it will run rich, if you have other things also causing it to go rich, it could be way too rich. But if the only problem was the O2s being disconnected, it should not cause the car to have a lack of power. Some people don't use them at all, the O2s are only used by the computer when it is in closed loop, so at WOT they are ignored. The MAF could easily be a problem, or could need to be tuned, I have found many Pro M meters that were way out of calibration, to the point they would hardly run, if at all. Do you have an adjustable fuel pressure regulator and if so what pressure is it adjusted to with the vacuum line disconnected? __________________ My car is an '85 sonic blue coupe with 302 bored and stroked to 364, Ported Twisted Wedge heads and a BXR intake, A9M ECM with a Tweecer, C4 with trans brake, Hoosier 275/60/15 drag radials, no power adders. The car is still street driven, with a best of 10.21 at 131 mph with a 1.51 60' spinning lightly. With this combo it made a best of 460 hp and 410 lbs of torque at the wheels.

08-05-2008, 01:47 PM	#16
coupe5oh Brewmeister Join Date: Nov 2004 Location: n.e. Sanantonio Posts: 420 Trader Rating: (0)	A guy came in to my work for with a cobra kit car, it had an efi 5.0 in it, It would barely stay started, i looked underneath and it had no 02's in it either, I told him, i didnt know how it was running as good as it was. __________________ retired 1990 Tx dps :T-5, stock bottom 302, shorty headers,o-r x-pipe, ported explorer true gt 40 heads, matching intake. E-cam 1.7's, pro-m 77, 24lb injectors, 3.90 gears. good for mid 12's on stickies.

08-05-2008, 09:32 PM	#17
95 GTS Back in the saddle again Join Date: Feb 2006 Location: Texas Posts: 1,710 Trader Rating: (0)	75mm are prone to be pieces of crap out of no where. First, make sure the meter is clucked where the electronics are on the outside of the curve of the coldair. second, throw it away or sell it and buy a pro M 80 and put that puppy in the fender well. It could be as simple as someone left the spout connector out when they set timing. Do you have a regulator on that bad boy to control that 255 walbro? __________________ 2007 Reflex Silver Wolfsburg Jetta - new hotness 1995 Canary Yellow GTS - Sold 12.81@106.2 w/1.80 60' Boltons/E303 + 3100 lbs + M&H 246 HP/ 290 TQ 12.57 @ 109.21 w/1.76 60' Boltons/GT40Ps/XE270 + 3240 lbs + 555Rs 295 HP / 321 TQ

08-05-2008, 10:58 PM	#18
fiveohfox Registered User Join Date: Nov 2007 Location: Katy, TX Posts: 9 Trader Rating: (0)	Have you done a compression check lately?

08-08-2008, 08:10 PM	#19
Angron2169 Registered User Join Date: Jan 2007 Location: Houston Posts: 140 Trader Rating: (0)	ok comopression is good fuel pressure is good cats are not clogged we are starting to lean towards the pmas mass air sensor it is calibrated for the injectors just a thought Thanks Allan __________________ 93 Mustang Cobra Clone- Sold 86 Mustang SVO- Sold 90 Mustang LX 2.3T- Sold 89 Mustang LX- Traded 64 Mustang 351W- Dynod 473hp

08-08-2008, 09:59 PM	#20
XavB Registered User Join Date: Sep 2003 Posts: 194 Trader Rating: (0)	did you pull the codes? or hook up the O2's? __________________ 1992 LX 5.0 - Twisted Wedge heads, Trickflow Stage 1 cam, Trickflow Streetburner Intake, Trickflow 1.6rr's, BBK shorty headers & o/r h-pipe, flowmaster catback, FRPP 4.10s, FRPP 24lb injectors, Granatelli MAF, BBK CAI, BBK 65mm throttle body, BBK FPR, Maximum Motorsports LCA's, CC plates, and strut tower brace, LMM full length SFC's, Mach 1 springs, and Bilstein shocks and struts

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