38k Hesitation ??'s

SoGlow7 · 03-25-2008, 07:44 AM

ok so i went through the FAQ's and i saw that this problem is most likely due to poor ground connections and/or fuel injectors. But this problem just started yesterday and it happened to me twice, so i just got a couple ?'s.. 1. The hesitation happened once when i was in 1st gear and again when i was in 3rd so can the hesitation happen in any gear? 2. When it hapened the car bogged down to about 1k rpm's and then shot back up all the way 7500 rpms, the rev buzzer beeped then the car died...

is this normal? 3.After the car shut off i waited like 7 seconds and the started right back up w/ no problems! Is this normal also? I'm assuming its the 3800 hesitation because after i drove all the way home w/out going over 3500 rpms, and the car was fine... so any answers help thanks!

classicauto · 03-25-2008, 07:58 AM

No, the situation you've described in #2 is NOT a normal 3800rpm hesitation.

The typical hesitation will appear as a burp while plowing through the revs, or pause in acceleration around 3800. It doesn't bring the motor to idle rpms, then redline.

I'd suggest checking/cleaning some of the grounds on the engine and inspecting the secondaries. Are they of known condtion?

85rx-7gsl-se · 03-25-2008, 09:53 AM

You 3800 right? Not 38000, them be some crazy revs man

$100T2 · 03-25-2008, 10:05 AM

Quote:

Originally Posted by SoGlow7

ok so i went through the FAQ's and i saw that this problem is most likely due to poor ground connections and/or fuel injectors. But this problem just started yesterday and it happened to me twice, so i just got a couple ?'s.. 1. The hesitation happened once when i was in 1st gear and again when i was in 3rd so can the hesitation happen in any gear? 2. When it hapened the car bogged down to about 1k rpm's and then shot back up all the way 7500 rpms, the rev buzzer beeped then the car died...

is this normal? 3.After the car shut off i waited like 7 seconds and the started right back up w/ no problems! Is this normal also? I'm assuming its the 3800 hesitation because after i drove all the way home w/out going over 3500 rpms, and the car was fine... so any answers help thanks!

What kind of FC is it? NA or turbo?

SoGlow7 · 03-25-2008, 08:00 PM

oh yeah it's an na gxl... i noticed the 38k after i posted.. but anyway i didnt think the revving was normal. Thats why i posted but, yeah i drove it all day today and it was fine. i've kept it under 3500 rpm's when driving so the 5th/6th ports stay closed, so maybe that may be where the problem is, since it hasnt happened since. I also noticed today the voltage meter on the dash will gradually drop as i take my foot off the gas pedal, but never under 8v.. when im on the gas it stays at constant 13v.. could that be tied in w/ the problem? but im hoping after re-grounding the car will run like a champ again..just wishful thinking anyway

My5ABaby · 03-25-2008, 08:06 PM

Do your lights and stuff get dim when it drops? That's a bit odd. I had an alternator do that but it would go past 13v the higher I got. It sure as hell made my lights really bright around 5k rpm's though!

SoGlow7 · 03-25-2008, 08:36 PM

no thats the wierd thing all my electrics were still on when the car died.. radio, dash and headlights! It wouldnt turn over the first couple of tries like it was flooded or somethin, but then after maybe a minute it fired right up

FerociousP · 03-25-2008, 08:50 PM

i forget which pin it is on the ecu, but i've fixed the hesitation twice (separate cars) regrounding the pin to the body right next to the ecu

SoGlow7 · 03-25-2008, 09:11 PM

I'll update over the weekend, after i re-ground. Then we'll see what happens from there

$100T2 · 03-25-2008, 09:19 PM

It's not the 3800 rpm hesitation. At first, it sounded like a boost related fuel cut-off, which is why I asked if it was a turbo or not. It sounds like you either have a clogged fuel filter, a shitty pump, or maybe your exhaust is clogged. If you hammer the throttle and it stalls, but go up slowly and it doesn't, that sounds like a fuel delivery problem to me.

SoGlow7 · 03-25-2008, 09:23 PM

ill look into that as well... i thought it was the 3800 because it happened right around 3800, but that might have been a coincidence. Just to confuse me a little more

Ender · 03-25-2008, 09:48 PM

Quote:

Originally Posted by SoGlow7

ill look into that as well... i thought it was the 3800 because it happened right around 3800, but that might have been a coincidence. Just to confuse me a little more

Well if it's a weak fuel pump then that would make some sense. The secondary injectors start firing at 3800RPM so it could drop the pressure too much for the pump to keep up unless maybe if you're easing past it (despite the fact that the same total amount of fuel should be nearly the same as just under 3800RPM).

Check your pulsation dampener if you get the chance, it's a common failure at this stage in these cars' lives and can cause engine fires <---BAD So yeah, check that out, hopefully you won't have to go out of your way to do so. It may be a little more accessible on the NA FC's.

SoGlow7 · 03-26-2008, 07:47 AM

roger

SoGlow7 · 03-26-2008, 04:41 PM

well today i went to put gas in my car, and when i twisted the gas cap.. alot of pressure came out of the gas tank. I didnt take tha cap all the way off till it was done letting out the pressure.. so yeah theres something wrong with the fuel system

My5ABaby · 03-26-2008, 04:47 PM

http://www.rx7club.com/showthread.ph...+tank+pressure

See reply #8 by Aaron.

03-25-2008, 07:44 AM	#1
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	38k Hesitation ??'s ok so i went through the FAQ's and i saw that this problem is most likely due to poor ground connections and/or fuel injectors. But this problem just started yesterday and it happened to me twice, so i just got a couple ?'s.. 1. The hesitation happened once when i was in 1st gear and again when i was in 3rd so can the hesitation happen in any gear? 2. When it hapened the car bogged down to about 1k rpm's and then shot back up all the way 7500 rpms, the rev buzzer beeped then the car died... is this normal? 3.After the car shut off i waited like 7 seconds and the started right back up w/ no problems! Is this normal also? I'm assuming its the 3800 hesitation because after i drove all the way home w/out going over 3500 rpms, and the car was fine... so any answers help thanks!

03-25-2008, 08:36 PM	#7
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	no thats the wierd thing all my electrics were still on when the car died.. radio, dash and headlights! It wouldnt turn over the first couple of tries like it was flooded or somethin, but then after maybe a minute it fired right up __________________ DD: 93' EG "Ferio" Sedan Project: 88' TII Rebuild Since Spring of 07'

03-25-2008, 09:11 PM	#9
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	I'll update over the weekend, after i re-ground. Then we'll see what happens from there __________________ DD: 93' EG "Ferio" Sedan Project: 88' TII Rebuild Since Spring of 07'

03-25-2008, 09:19 PM	#10
$100T2 Big Daddy Join Date: Feb 2008 Location: Rhode Island iTrader: (2) Posts: 419 Rep Power: 17	It's not the 3800 rpm hesitation. At first, it sounded like a boost related fuel cut-off, which is why I asked if it was a turbo or not. It sounds like you either have a clogged fuel filter, a shitty pump, or maybe your exhaust is clogged. If you hammer the throttle and it stalls, but go up slowly and it doesn't, that sounds like a fuel delivery problem to me. __________________ Hell hath no fury like a rotor blown.

03-25-2008, 09:23 PM	#11
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	ill look into that as well... i thought it was the 3800 because it happened right around 3800, but that might have been a coincidence. Just to confuse me a little more __________________ DD: 93' EG "Ferio" Sedan Project: 88' TII Rebuild Since Spring of 07'

03-25-2008, 07:58 AM	#2
classicauto crash auto?fix auto Join Date: Feb 2008 iTrader: (0) Posts: 816 Rep Power: 17	No, the situation you've described in #2 is NOT a normal 3800rpm hesitation. The typical hesitation will appear as a burp while plowing through the revs, or pause in acceleration around 3800. It doesn't bring the motor to idle rpms, then redline. I'd suggest checking/cleaning some of the grounds on the engine and inspecting the secondaries. Are they of known condtion?

03-25-2008, 08:00 PM	#5
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	oh yeah it's an na gxl... i noticed the 38k after i posted.. but anyway i didnt think the revving was normal. Thats why i posted but, yeah i drove it all day today and it was fine. i've kept it under 3500 rpm's when driving so the 5th/6th ports stay closed, so maybe that may be where the problem is, since it hasnt happened since. I also noticed today the voltage meter on the dash will gradually drop as i take my foot off the gas pedal, but never under 8v.. when im on the gas it stays at constant 13v.. could that be tied in w/ the problem? but im hoping after re-grounding the car will run like a champ again..just wishful thinking anyway

03-25-2008, 08:06 PM	#6
My5ABaby Sigh..... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (6) Posts: 2,377 Rep Power: 19	Do your lights and stuff get dim when it drops? That's a bit odd. I had an alternator do that but it would go past 13v the higher I got. It sure as hell made my lights really bright around 5k rpm's though!

03-25-2008, 08:50 PM	#8
FerociousP I-had-a-bad-experience... Join Date: Feb 2008 Location: M'boro iTrader: (2) Posts: 1,046 Rep Power: 18	i forget which pin it is on the ecu, but i've fixed the hesitation twice (separate cars) regrounding the pin to the body right next to the ecu

03-26-2008, 07:47 AM	#13
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	roger __________________ DD: 93' EG "Ferio" Sedan Project: 88' TII Rebuild Since Spring of 07'

03-26-2008, 04:41 PM	#14
SoGlow7 Rotary Fan in Training Join Date: Feb 2008 Location: Big Red Country iTrader: (1) Posts: 58 Rep Power: 17	well today i went to put gas in my car, and when i twisted the gas cap.. alot of pressure came out of the gas tank. I didnt take tha cap all the way off till it was done letting out the pressure.. so yeah theres something wrong with the fuel system __________________ DD: 93' EG "Ferio" Sedan Project: 88' TII Rebuild Since Spring of 07'

03-26-2008, 04:47 PM	#15
My5ABaby Sigh..... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (6) Posts: 2,377 Rep Power: 19	http://www.rx7club.com/showthread.ph...+tank+pressure See reply #8 by Aaron.