syclone

For 2005 I decided to use my accord for autocross competition. During one practice session and the championship following, the engine has a big hesitation during fast transitions from one side to the other (like a high speed slolam). It feels as if vtec refuses to switch over for a while.

My brother and another friend suggested that it could be an oil starvation problem.. I just wanted to get more opinions before I take any action.

Thanks in advance.

krshultz

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by syclone &raquo;</TD></TR><TR><TD CLASS="quote">My brother and another friend suggested that it could be an oil starvation problem.. I just wanted to get more opinions before I take any action.

Thanks in advance.</TD></TR></TABLE>

That's the first place I'd look and also the easiest to check. Overfill the motor by a quart and see if the problem goes away.

oxycotton

IIRC, vtec only enguages if the motor has load on it, it's up to temp. and if it has enough oil presure to activate the vtec silonoid. I'd guess oil startvation, but only off by a little bit.

ryan12321

it also won't go into vtec under certain fuel starvation issues as well. Its happened to me in my car. It has to be VERY VERY low to do this though.

travis

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by krshultz &raquo;</TD></TR><TR><TD CLASS="quote">

That's the first place I'd look and also the easiest to check. Overfill the motor by a quart and see if the problem goes away.</TD></TR></TABLE>

I'm curious how low the pressure has to go before VTEC won't engage. I never had this problem in the ITR but I kept the oil level just over "full." For those of you with oil pressure gauges, have you ever looked at the pressure when the motor drops out of VTEC?

Chris F

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by syclone &raquo;</TD></TR><TR><TD CLASS="quote">For 2005 I decided to use my accord for autocross competition. During one practice session and the championship following, the engine has a big hesitation during fast transitions from one side to the other (like a high speed slolam). It feels as if vtec refuses to switch over for a while.

My brother and another friend suggested that it could be an oil starvation problem.. I just wanted to get more opinions before I take any action.

Thanks in advance.</TD></TR></TABLE>

If it is a big hesitation, it's probably fuel. Was your fuel tank below half-way? Did you fill gas between practice and championship runs?

I starve in carousels when the tank is below half-way.

-Chris

Mohudsolo

Gas level would be my first choice too. Civics often have this issue when Integras usually don't. My guess is the Integra has more baffling in the tank. Assuming what Honda expects the typical user to be in the Accord, I would expect little baffling in that tank too.

syclone

i was almost exactly at half tank.. never really thought about fuel starvation.. that sucks..

my oil is exactly at the half way point as well on the dip stick.. so i'll i'll probably try filling it up to full..

much appreciated on the advice..

fsp31

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mohudsolo &raquo;</TD></TR><TR><TD CLASS="quote">Gas level would be my first choice too. Civics often have this issue when Integras usually don't. My guess is the Integra has more baffling in the tank. Assuming what Honda expects the typical user to be in the Accord, I would expect little baffling in that tank too.</TD></TR></TABLE>

That's weird. I'm not doubting, but it's strange that experiences with fuel starvation are so varied. I autoxed my 98' Civic hatch for 6 years on 9" wide wheels shod in Hoosiers (CSP, FSP, and finally SM), and never once experienced fuel starvation. My fuel "ritual" was to run the tank as dry as I could, then put in 2 gallons of gas. The fuel light would barely be off. Never had a single problem on any course.

Chris F

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fsp31 &raquo;</TD></TR><TR><TD CLASS="quote">That's weird. I'm not doubting, but it's strange that experiences with fuel starvation are so varied. I autoxed my 98' Civic hatch for 6 years on 9" wide wheels shod in Hoosiers (CSP, FSP, and finally SM), and never once experienced fuel starvation. My fuel "ritual" was to run the tank as dry as I could, then put in 2 gallons of gas. The fuel light would barely be off. Never had a single problem on any course.</TD></TR></TABLE>

Yeah, I would usually autocross with the gas light on and not have problems either! The ONLY time I've seen it was on long sweepers. Actually, an exit ramp too (and I wasn't really driving spiritedly either!!!)

The ITR gas tank is baffled less than the GSR (weight savings), FWIW.

-Chris

Mohudsolo

A bunch of the national caliber STS 89 Si's run half tank or more to prevent starvation, then other people with the same car have no issues down to near dry. I don't get it either. I say we get everyone who has starvation issues and everyone who does not together and drop all the tanks and answer the question once and for all. Don't forget the no smoking sign.

It seems like I have heard it more with the older model cars than the newer ones, so there may have been changes in the systems. My old 86 RX-7 could not run lower than 1/4 tank on concrete without sucking wind and I would have assumed Mazda expected that car to be thrown around some.

rice_classic

One word... Slosh.

Jaker

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rice_classic &raquo;</TD></TR><TR><TD CLASS="quote">One word... Slosh. </TD></TR></TABLE>

Yup. Its either next to empty (1/4 or less) or full. The slosh can lead to unpredictable handling with 1/2-2/3 of a tank. Thats alot of weight tossing around back there. Can you say "pendulum effect"?

f1nal zeros

I had this same problem happen to me in my rsx type s. Oil starvation was lagging my motor. Vtec was to engage at 6k and it engaged at 71oo. Car felt as if I hit a hard patch of air and my car would lag bad then struggle to keep it.

Pulled off the track and checked the oil. I could not find it on the dipstick. I add 2 qts. and it barely reached the first dot.

Add oil and got back on the track and the problem was gone. You may just want to check your oil bro.

bb6h22a

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by syclone &raquo;</TD></TR><TR><TD CLASS="quote">i was almost exactly at half tank.. never really thought about fuel starvation.. that sucks..</TD></TR></TABLE>

I usually run my car (on the track) with a little more than 1/2 a tank because I've noticed that with R compounds and quick, high load direction changes you can get fuel to starve. Whoever said a big cutout is fuel is right; it feels as though you've turned the car off and on while cornering.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">my oil is exactly at the half way point as well on the dip stick.. so i'll i'll probably try filling it up to full..</TD></TR></TABLE>

I keep the oil overfilled by 0.25 to 0.5 qts througout the day - the last thing you want is a spun road bearing etc.

It's cheap insurance.

Chris F

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bb6h22a &raquo;</TD></TR><TR><TD CLASS="quote">I keep the oil overfilled by 0.25 to 0.5 qts througout the day - the last thing you want is a spun road bearing etc.

It's cheap insurance.
</TD></TR></TABLE>

Tech question/thread jack:

At what point is overfilling oil going to do damage? When you start sucking oil through the PCV? I've always heard "DON'T OVERFILL YOUR OIL OR YOU'LL RUIN YOUR ENGINE".... which is obviously partially true, but what's the limiting factor on the overfill?

I run my car at "full", never overfill. But I'm considering changing my policy, at least for HPDE or beginning long highway trips.

Thanks!
Chris

syclone

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">

Tech question/thread jack:

At what point is overfilling going to do damage? When you start sucking oil through the PCV? I've always heard "DON'T OVERFILL YOUR OIL OR YOU'LL RUIN YOUR ENGINE".... which is obviously partially true, but what's the limiting factor on the overfill?

I run my car at "full", never overfill. But I'm considering changing my policy, at least for HPDE or beginning long highway trips.

Thanks!
Chris
</TD></TR></TABLE>
i heard that too until this thread.. that's why i kept it around the middle. i'll at least try up to the full line to see if that helps.. if that doesn't work, i'll try filling the fuel to 3/4's.. although i'd like to avoid this.. i guess i'll have to let you guys know next month what it turns out to be since i can't really experiment on the streets

bb6h22a

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">

Tech question/thread jack:

At what point is overfilling oil going to do damage? When you start sucking oil through the PCV? I've always heard "DON'T OVERFILL YOUR OIL OR YOU'LL RUIN YOUR ENGINE".... which is obviously partially true, but what's the limiting factor on the overfill?

I run my car at "full", never overfill. But I'm considering changing my policy, at least for HPDE or beginning long highway trips.

Thanks!
Chris
</TD></TR></TABLE>

I don't have an empirically determined, scientific, factual volume to tell you; eg, at 1.71222 qts over, your engine will implode, fart out a connecting rod and poke both cams through the hood.

My personal "rule of thumb" has always been that 0.5qts over is "safe." That comes from 30 or so track days of running my car 0.5 qts over.

Moreover I've yet to see an engine fail at the track (in the aforementioned manner) from being overfilled. But have seen more than one engine fail from being run dry or experiencing starvation.

rice_classic

When you run too much oil (way too much) it will either suck it through the pcv or in most cases blow the seals.

The chances of having camshafts shoot through your hood from over filling your oil is very minimal. The seals will blow WAY before other damage is done.

turfer

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rice_classic &raquo;</TD></TR><TR><TD CLASS="quote">The chances of having camshafts shoot through your hood from over filling your oil is very minimal. </TD></TR></TABLE>

I would like to be around to see this happen though.

Mohudsolo

That brings up a question I can never get answered: Do the fenders fly off if a Subaru blows the engine? I really want to know.

I generally run my GSR at full to 1/4 qt over full and have had zero issues. As far as gas, I've had the low fuel light come on 1-2 miles after leaving the track and never had any hesitation on track, either autox or track school.