38k Hesitation ??'s

[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!

[classicauto]

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]

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

[$100T2]

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]

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 :o15:

[My5ABaby]

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! :D

[SoGlow7]

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]

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]

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

[$100T2]

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]

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]

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]

roger

[SoGlow7]

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]

http://www.rx7club.com/showthread.php?t=664251&highlight=gas+tank+pressure

See reply #8 by Aaron.

[SoGlow7]

The car died on me on the way to work today.. once when i hit a pot hole, it bogged down.. and wouldnt respond to the gas pedal, but then kicked back up after about 2 seconds and accelerated as normal. Then again when i was at about 3k pms doin 80 in 5th on the freeway.. the rpm gauge started flyin around all crazy, bouncin everywhere. The car did not shut off this time but it still wouldn't accelerate.. it slowed to about 40 mph on the shoulder, i then put it in 4th and the car took off again fine. Made it the rest of the way to work.. So i decided to car pool from now on while i rip her guts open and see whats goin on.. starting with the fuel delivery