4500 RPM Stutter/Miss - ZR-1 Net Registry Forums

bobbyhi · 05-03-2008

When I took the Z out today it would stutter/miss at 4500 rpm and up.
The gas is fresh and the injectors just come back from RC for cleaning and R&R. I really don't know where to start. Could be fuel problem??? Could be vaccum??? Could be electrical???? Something not hooked up right??? Any suggestions will be helpful.

Kevin · 05-03-2008

could be actuators could be vaccum

05-03-2008

Bob, does it do it in both full power and normal power modes?

bobbyhi · 05-03-2008

Quote:

Originally Posted by Jeffvette

Bob, does it do it in both full power and normal power modes?

Didn't try it in the normal mode - too late in the day. I'll try that tomorrow and let you know.

bldavis11 · 05-03-2008

Quote:

Originally Posted by bobbyhi

When I took the Z out today it would stutter/miss at 4500 rpm and up.
The gas is fresh and the injectors just come back from RC for cleaning and R&R. I really don't know where to start. Could be fuel problem??? Could be vaccum??? Could be electrical???? Something not hooked up right??? Any suggestions will be helpful.

If it were vacuum, you should experience problems earlier in the RPM band depending on how aggressive you are with the right foot. Regardless, you'll see problems when you're in the 3K range. Likewise and electrical problem should always be there. The sparks aren't any bigger! My vote is for inadequate fuel pressure, likely secondary (no pun intender) to the pumps.

32valvZ · 05-04-2008

Heres my limited input.....possibly crossed an igniton wire at one of the the coils,(if they were removed) bad secondary vacume actuators/linkage.

bobbyhi · 05-04-2008

I rehooked a vaccum line that was loose and seems to be working fine now. I tried it in the normal mode and never realized just how slow the car runs in that mode. Put her on full power and she was screaming for more

Thanks guys for your suggestions.

Paul Workman · 05-04-2008

Quote:

Originally Posted by bobbyhi

I rehooked a vaccum line that was loose and seems to be working fine now. I tried it in the normal mode and never realized just how slow the car runs in that mode. Put her on full power and she was screaming for more

Thanks guys for your suggestions.

For the record, which vacuum line was it that you reconnected? Just curious. (Before you said a vacuum line, I was focused on whether the secondary fuel pump was running. SO! The vacuum thing was a bit of a surprize (to me), if it was anything other than one of the MAPs.

P.

bobbyhi · 05-04-2008

The line that comes from under the plenum and connects about half way into the plenum on the drivers side.

05-03-2008	#1
bobbyhi Join Date: Jul 2005 Location: Mendota Heights, MN. 55120 Posts: 984	4500 RPM Stutter/Miss When I took the Z out today it would stutter/miss at 4500 rpm and up. The gas is fresh and the injectors just come back from RC for cleaning and R&R. I really don't know where to start. Could be fuel problem??? Could be vaccum??? Could be electrical???? Something not hooked up right??? Any suggestions will be helpful. __________________ Bob Anderson 1990 #2405 White/Gray Haibeck chip,4:09 gears,Power Effects Exhaust,5 spoke chrome,C5 brakes,49th Street rockers,K&N,Hurst,Headers,Upper & lower ported Minnesota State Director Founding Member #19

05-03-2008	#2
Kevin Join Date: Jun 2005 Location: pittsburgh Posts: 4,633	Re: 4500 RPM Stutter/Miss could be actuators could be vaccum __________________ It's not the car, it's the people - Doug Johnson 90 r/r "KEYS ON" nick named "T.L.B"

05-03-2008	#3
Jeffvette Guest Posts: n/a	Re: 4500 RPM Stutter/Miss Bob, does it do it in both full power and normal power modes?

05-04-2008	#6
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,071	Re: 4500 RPM Stutter/Miss Heres my limited input.....possibly crossed an igniton wire at one of the the coils,(if they were removed) bad secondary vacume actuators/linkage. __________________ [B]1990 #2815[/B] [COLOR="Red"][B]Red/Red[/B][/COLOR] Ported Plenum & IH (by Pete) Haibeck Chip Rebuilt FPR (by Phil) FIC Injectors Watson LT Headers 3" Stainless Works exhaust Lingenfelter Open Air Lid Bill B Built Transmission Shifter & C Beam Plates [FONT=Impact][COLOR=red]1992 [COLOR=black]#[/COLOR] 091[/COLOR][/FONT] [FONT=Impact][COLOR=#ff0000]Red/[COLOR=silver]Gray[/COLOR][/COLOR][/FONT] [B]SOLD[/B]

05-04-2008	#7
bobbyhi Join Date: Jul 2005 Location: Mendota Heights, MN. 55120 Posts: 984	Re: 4500 RPM Stutter/Miss I rehooked a vaccum line that was loose and seems to be working fine now. I tried it in the normal mode and never realized just how slow the car runs in that mode. Put her on full power and she was screaming for more Thanks guys for your suggestions. __________________ Bob Anderson 1990 #2405 White/Gray Haibeck chip,4:09 gears,Power Effects Exhaust,5 spoke chrome,C5 brakes,49th Street rockers,K&N,Hurst,Headers,Upper & lower ported Minnesota State Director Founding Member #19

05-04-2008	#9
bobbyhi Join Date: Jul 2005 Location: Mendota Heights, MN. 55120 Posts: 984	Re: 4500 RPM Stutter/Miss The line that comes from under the plenum and connects about half way into the plenum on the drivers side. __________________ Bob Anderson 1990 #2405 White/Gray Haibeck chip,4:09 gears,Power Effects Exhaust,5 spoke chrome,C5 brakes,49th Street rockers,K&N,Hurst,Headers,Upper & lower ported Minnesota State Director Founding Member #19