RPMS still act VERY funny past 3k
03-10-2001, 01:52 PM
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RPMS still act VERY funny past 3k
Ok, ever since I've had my blower my RPMS have acted funny past 3k. They very eratically hover back and forth.
Someone suggested I was running lean, well now I have put my stock prom in and my 02 sensor readings are in the mid 900s and it has not helped the problem AT ALL! I have 24# injectors. It was even doing this on a custom prom made for the blower. What the hell is going on. I recently did a tune up. My rotor, plugs (R43TS), wires (9mm), cap are all brand new. My MSD6AL wires were soldered so I know that can't be it. And even my MSD blaster coil is brand new. What could it be??? It even does it now without the blower!! could it be the new coil?
The only codes I am getting are 32. Which is EGR.
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91 Formula
305 TPI 5speed
1LE/G92/WS6
Paxton SN92 polished kit, SLP airfoil, ported/polished plenum, March pulleys, Crane AFPR(43psi),Crane Gold 1.6rrs,MSD coil,MSD6AL (5200rpm limit),Holley 9mm wires,Ac delco R43ts plugs,stock chip,Ford SVO 24# injectors,Bosch O2sensor,SLP 1 5/8" headers,SLP catback,shortened shifter,3:73s w/Auburn posi,170* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
[This message has been edited by theformula (edited March 10, 2001).]
Someone suggested I was running lean, well now I have put my stock prom in and my 02 sensor readings are in the mid 900s and it has not helped the problem AT ALL! I have 24# injectors. It was even doing this on a custom prom made for the blower. What the hell is going on. I recently did a tune up. My rotor, plugs (R43TS), wires (9mm), cap are all brand new. My MSD6AL wires were soldered so I know that can't be it. And even my MSD blaster coil is brand new. What could it be??? It even does it now without the blower!! could it be the new coil?
The only codes I am getting are 32. Which is EGR.
------------------
91 Formula
305 TPI 5speed
1LE/G92/WS6
Paxton SN92 polished kit, SLP airfoil, ported/polished plenum, March pulleys, Crane AFPR(43psi),Crane Gold 1.6rrs,MSD coil,MSD6AL (5200rpm limit),Holley 9mm wires,Ac delco R43ts plugs,stock chip,Ford SVO 24# injectors,Bosch O2sensor,SLP 1 5/8" headers,SLP catback,shortened shifter,3:73s w/Auburn posi,170* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.
[This message has been edited by theformula (edited March 10, 2001).]
03-10-2001, 05:16 PM
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Car: 1991 Formula L98
Engine: 350
Transmission: T-56
Axle/Gears: 3.73:1
You mean the tach acts funny past 3k? Then it's the MSD box.. they sell a tach filter that cures it. For some reason, the stock tach acts funny when you use an MSD box, although I have heard aftermarket tachs work fine (when they are connected to the tach output on the MSD box)...
03-11-2001, 04:10 AM
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Is it the tach jumping around, or are you losing power (HP) also?
03-11-2001, 03:56 PM
#4
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theformula,
There is a MSD tech that is a member here, if you think the problem is in the MSD Box email Joe (MSDTECH) at: msdtech@msdignition.com
He's extremely helpfully...
Have you tried bypassing the MSD box and seeing if the problem still exists???
------------------
MÅN¡ÅÇ ©
88 IROC 5.7L,edelbrock TES,random tech cat,borla exhaust,chip,sfc,accel wires,airfoil,k&n's,ETC..
and NOW supercharged!!!
http://maniac.megamania.com
There is a MSD tech that is a member here, if you think the problem is in the MSD Box email Joe (MSDTECH) at: msdtech@msdignition.com
He's extremely helpfully...
Have you tried bypassing the MSD box and seeing if the problem still exists???
------------------
MÅN¡ÅÇ ©
88 IROC 5.7L,edelbrock TES,random tech cat,borla exhaust,chip,sfc,accel wires,airfoil,k&n's,ETC..
and NOW supercharged!!!
http://maniac.megamania.com
03-11-2001, 11:54 PM
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Car: '86 IROC-Z + Misc. project cars.
Engine: Supercharged + Nitrous TPI 355 CID
Transmission: Art Carr built Th700r4
I agree. You have eliminated fueling as the cause (or only cause at least). If you haven't bypassed the MSD and tried it that way then do that and verify that it is, or definitely is not related to the ignition box.
------------------
Tracy /AKA IROCKZ4me
'86 IROC-Z Camaro
"Cogito ergo zoom"
EFI Performance Club on Yahoo
Club IROC-Z
[This message has been edited by IROCKZ4me (edited March 11, 2001).]
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Tracy /AKA IROCKZ4me
'86 IROC-Z Camaro
"Cogito ergo zoom"
- 355 cid
- AFR heads
- Arizona Speed & Marine hydraulic roller cam w/ AFR hydra-rev kit
- modified SLP runners
- TRW forged pistons/ceramic coated
- fully balanced
- Edelbrock headers/ceramic coated
- SLP cat-back
- Paxton supercharger
- Nitrous Express nitrous oxide
EFI Performance Club on Yahoo
Club IROC-Z
[This message has been edited by IROCKZ4me (edited March 11, 2001).]
03-12-2001, 10:30 AM
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Car: 87 Iroc
Engine: Turbocharged 5.7 Pro-Fl-XT
Transmission: 700R4 for moment
Axle/Gears: 3.25 9 inch
This is a long shot.. what tachometer are you using? My stock tach started causing a similar problem out of the blue.. The only hint I had that it was the tach was that it started running backwards when I went over 5500 rpm. It took me a few tries to figure out the tach was the cause. Of course I wasn't running a MSD box, so my tach was plugged directly into the distributor tach feed.
steve
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