REVscene Automotive Forum - throttle bogging/hesitating problem

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throttle bogging/hesitating problem

I have a 92 gsr
that seems to have a problem that cannot be solved

sometimes when I drive the car the car bogs/hesitates to accelerate in the 2-3k rpm range. I can feel the car as almost if the brakes have been lightly applied and the throttle gets heavy and will not accelerate unless i floor it even then it takes a bit for it to get out of this sticky rpm range. I have this problem about 50% of the time
sometimes when i start the car its zippy and responsive other times i really have to give it gas to get it going and drives like a slug

Ive clean the tb, changed plugs n wire, distrib cap n rotor, o2 sensor, reset the ecu and still get the problem
maybe something to do with tps?

anybody got any ideas?

Quote:

Originally Posted by kookoobird88 (Post 8204248)

Dirty MAF?

Could be a fuel delivery problem
Posted via RS Mobile

First instinct tells me cat converter.

fuel filter could be really dirty, injectors as well.

I don't believe my car has a MAF sensor.
I have a fairly new cat. And I changed the fuel.filter as well.
I could try maybe try some fuel injector cleaner.
Posted via RS Mobile

My truck was doing weird shit like that when the TPS went. When it's being boggy is it very erratic and jerky or does it still drive smoothly.

When it hits the rough patch the car almost does like a small jerking motion. And the car just doesn't want to accelerate. I have to floor it to get past that rough range. Once its past it the car takes off. So to answer your question it still drives semi smooth but almost like its cutting out
Posted via RS Mobile

Quote:

Originally Posted by kookoobird88 (Post 8204568)

Ya sounds like what my truck did when the TPS/ECM went. My ECM was the culprit but it was cutting/screwing up my TPS.

Also, TPS tend to go "bad" in the rpm range that you spend the most time within. For my diesel you'll usually be all fucked up between 1500-2000 rpms as that's the "normal" operating range. If they are a cheap part for your car i would think about putting one in. Then again, i've never owned a Honda and this is all speaking off experiences with my truck haha.

I'm gonna order a Tps sensor its around 60$
I just put some injector cleaner in.
I was gonna get bigger injectors so I don't know if I should get someone to clean mine or.just put new ones in
Also going to try and trace the wiring from the tps to make sure no connections are corroded or dirty. So annoying when the car doesn't drive the same everytine u turn it on and off
Posted via RS Mobile

Id check the tps as well

i just spent 4 months trying to solve a similar issue on my 09 mitsu ralliart.

i upgraded the fuel pump and fuel rail, but the pump i upgraded to didn't have a built in fuel damper like the stock one. At 2200-2500 rpm the car was going super lean and would hesitate same as yours.

Putting the stock fuel rail back on made the lean spot change to around 1500 rpm due to the change in size, but made the car infinitely more driveable. I have a subaru in-line fuel damper on order to hopefully solve the problem for good. I found other people online with the same issue, but in a few cases it was just because they had a faulty fuel damper, not from aftermarket parts.

this link has the technical explanation: [Supras] fuel dampner

Quote:

The FPD is in place for a couple of reasons, first to dampen
pulsation at high rpm and, second, to dampen the noise created by
fuel pulsing within the fuel rail that might be detected inside the
cockpit. Did you know that there is a screw in the top of the stock
FPD that allows a minor degree of adjustment? - refer to the TSRM
to check for proper operation. This screw (below the removable
plastic dome cover) was a topic of discussion on the List. Back in
2000, Larry Anderson adjusted his screw and, I believe, his fuel
pressure varied a few psi (I believe his observation was: No visible
fluxions. Screw was tight, so large movements of the screw weren't
possible. 1/2 turns @ most. Variation from loose to tight was from:
32psi to 38psi).

At any rate, here are my thoughts concerning fuel pulsation. The
pulsating of an injector initiates oscillation in the fuel system. The
flow of fuel through the injector is at high pressure during the intake
stroke of the engine, but then after its duration time is complete, the
pintle slams shut; what the fuel rail see at the injector takeoff is an
initial high flow and then a sudden disruption of that dynamic flow
when the pintlel closes, which causes first a drop of pressure in the
rail at the inlet to the injector (when pintle is open) and then a
buildup of pressure when the pintle closes due to disruption of the
dynamic flow of fuel being "cut off.". This is what initiates the
oscillation in fuel rail. As the pintle opens the fuel flow is again
deflected and the cycle is repeated. This oscillation is occurring at
different increments due to ignition order; some of the open/closing
pintles might cancel out or dampen the oscillation/wave effect and
others may reinforce the oscillation; we need a real design tech to
know for sure. If, at the instant when the pintle opens again, the
pressure wave in the fuel rail is moving toward the injector takeoff,
the fuel is at the boost pressure as it enters the injector and all is
well; the system is now said to be in a state of resonance. However,
if the pressure wave is away from the injector takeoff when then
pintle opens, then a reduced fuel pressure is being provided to the
injector. Evidently, the fuel rail will only be in resonance (i.e., in-
sync with a majority of the injectors) at one particular engine speed.
At other engine speeds, the volumetric efficiency will be lower.
Long fuel rail lengths provide good charging at high rpms, whereas a
short fuel rail would be better at relatively low engine rpms. The
development of oscillation and resonance is counteracted by the flow
resistance of the fuel rail (bigger might be better) and, perhaps, the
dampening effect of the FPD (fuel pressure dampener). Some
performance engines I have seen have two fuel rails, on short and
one larger and longer.

Thx for the info
I do have a aftermatket fuel rail IM and TB.
So maybe my fuel damper problem?
Or maybe a proper tune?
Posted via RS Mobile

if you have your stock fuel rail, and can put it back on, it should be immediately obvious if thats the problem as it will probably change the rpm range of the lean. Assuming its a different size/diameter than your current rail. Hooking up a wideband would probably tell you a fair bit as well.

pull the coil pack and check the condition
check if tps is within spec
any vacuum leaks?
old fuel? was the car stored at one point?
have u ever changed the fuel pump? hook up a fuel pressure gauge

Check fuel pressure, if ok, replace distributor

I have a fuel pressure gauge on the fuel rail, what type of reading should i get?
i used some fuel injector gum remover, hasnt done the problem since, maybe coincidence?
Im still probably gonna change the tps, and might get the injectors cleaned
the car was driving good tonight, good throttle response and def more torquey then usual

See how long that lasts. Don't change shit you don't need to.
Posted via RS Mobile

I would vote on TPS as well. The car is unable to determine whether it should run open loop (WOT) or closed loop given the input signal.

it may be one of those cases where the sensor is sending wrong signal instead of no signal.

had the same problem with my ITR....

replaced TPS and it was fine afterwards.

had an apexi VAFC controller that also had reading for throttle % input.

when my tps started to fail, noticed it the reading kept fluctuating, and sometimes no reading...

thanks for the input guys
Ill hopefully get a new one in the next week
and post an update

g5 might have those blox tps in stock
Posted via RS Mobile

Do you have a aftermarket exhaust or leaking exhaust pipes?

So I got the tps changed
Gotta go back to the shop cause the check engine light is on now. Anyways on the drive the car still
Did the bogging n hesitation again......fuuuu
What is the problem!??

I'm thinking I may have to take it to the Acura dealership but shop rate is $$$$$
Just drive it again and it barely accerlates in the 2-3k rpm range takes like 7-10secs to get from 2-3k....
Is there a way to see if the car is sending a code?
Maybe MAP sensor?
Posted via RS Mobile

I had this problem on the ITR when my primary o2 sensor took a shit on me. Replaced it and all was OK.