Decelleration issue. Any idea?

Dan fnuts

Hi everyone. I have an issue and i was hoping someone might be able to point me in the right direction. So when im on the motorway and i take my foot off the gas the car starts to decelerate. Its like the breaks are a little on.but if i put my foot down on the clutch the car is fine. Any idea?

(Forgive any spelling errors, im typing on my phone)

The Sidewards Man

Make, model, year, engine would be a huge asset to assist you.

JoseJones

Sounds normal to me

RustyNut

Sounds like normal engine braking to me.

Special Circumstances

Physics dude. Physics.

Dan fnuts

I have a Toyota Celica, 7th gen, 2004, 1.8L 1ZZ-FE engine. I was was driving a different 7th Gen Celica the other day and the same issues didn't happen. In My car if i tap my foot on and off the accelerator its like tapping on and off the breaks. you are push ed forward and backward in the seat. It sounds like the breaks but when the clutch is disengaged the car slows down more naturally and gradually.

savagethegoat

unless the other Celica was an auto, you must therefore have a sticking brake.

Disengaging the clutch will prevent engine braking, rendering slowing less natural and deceleration less rapid, perhaps made to feel normal by a sticking brake?

biko

After a drive, go around and touch all the alloys. If one is hotter than the others you have a sticking caliper on the brake.

Dan fnuts

I went for a drive and there wasn't more heat coming off a caliper/break than another. So if its Engine Breaking, can it be adjusted?

JoseJones

If it's engine braking then no, it's normal.

What gear are you driving in when it happens? How fast is the deceleration? At motorway speed in 5th/6th gear you shouldn't be decelerating that hard when you ease off the gas.

Cee-Jay-Cee

Dan fnuts wrote: »

I went for a drive and there wasn't more heat coming off a caliper/break than another. So if its Engine Breaking, can it be adjusted?

The wheels should be relatively cold. If the wheels (NOT the brake calipers) are warm/hot then you have an issue with your brakes.

Dan fnuts

JoseJones wrote: »

If it's engine braking then no, it's normal.

What gear are you driving in when it happens? How fast is the deceleration? At motorway speed in 5th/6th gear you shouldn't be decelerating that hard when you ease off the gas.

I only notice it when driving at high speed. So for example i would be driving on the motorway in 6th gear going 120Km. When i take my foot off the gas there is like a jerk and the car decelerates quite quickly. The faster you are when you take off the gas the quicker the deceleration happens. If it was the brakes then this effect would happen when i pushed the clutch down and disengaged it but it doesn't. So i am thinking it is engine related, Just don't what part

Dan fnuts

Cee-Jay-Cee wrote: »

The wheels should be relatively cold. If the wheels (NOT the brake calipers) are warm/hot then you have an issue with your brakes.

A few months ago i replaced 3 of the four break calipers and since then i have installed new break pads on them all. When i get back from a drive the wheels are not hot and the breaks give of a little heat but not much, also the heat temp feels the same on all of them.

mickdw

At motorway speeds, the difference between lifting off in gear and clutching should not be massive.
Is there any possibility that you have a heavily modified engine? Some mods could alter engine braking.
Does it happen in all gears - it should be most noticeable in lower gears?

Alternatively, it's a gearbox problem.

Dan fnuts

mickdw wrote: »

At motorway speeds, the difference between lifting off in gear and clutching should not be massive.
Is there any possibility that you have a heavily modified engine? Some mods could alter engine braking.
Does it happen in all gears - it should be most noticeable in lower gears?

Alternatively, it's a gearbox problem.

there is a definite difference and you can tell. The Engine is standard and not modified in any way. It happens in other gears but not as noticeable as when going motorway speeds.

If its a gearbox issue would you have any suggestions of things i could check to confirm that?

JoseJones

Dan fnuts wrote: »

I only notice it when driving at high speed. So for example i would be driving on the motorway in 6th gear going 120Km. When i take my foot off the gas there is like a jerk and the car decelerates quite quickly. The faster you are when you take off the gas the quicker the deceleration happens. If it was the brakes then this effect would happen when i pushed the clutch down and disengaged it but it doesn't. So i am thinking it is engine related, Just don't what part

That is very strange, 6th gear shouldn't be too dissimilar to holding in the clutch like mickdw says. Agree with you there, definitely not a brake issue. I would suspect it's a gear issue but I can't add anything more unfortunately, sorry.

kyote00

if its a temporary slow down or 'lurch' when you take your foot of the accelerator, then it might be the engine mounts are a bit worn.....

Had a similar issue in a corolla tsport a few years ago...

mudabi

kyote00 wrote: »

if its a temporary slow down or 'lurch' when you take your foot of the accelerator, then it might be the engine mounts are a bit worn.....

Had a similar issue in a corolla tsport a few years ago...

Great suggestion. I was mithering myself with other possible causes but forgot to start at the beginning.

Dan fnuts

kyote00 wrote: »

if its a temporary slow down or 'lurch' when you take your foot of the accelerator, then it might be the engine mounts are a bit worn.....

Had a similar issue in a corolla tsport a few years ago...

Good idea. I will check that out tomorrow. Thanks for the suggestion.

Dan fnuts

*UPDATE*
The problem is sorted. The issue was that the Fuel Filter in the Fuel tank was partially clogged with dirt. cleaned out and working 100% now. weird that, that was the issue but happy its fixed

biko

Sound, thanks for updating us

Machinestalker

As stated in 2nd post from The Sidewards Man........ Make, Model, Year......

s15r330

Machinestalker wrote: »

As stated in 2nd post from The Sidewards Man........ Make, Model, Year......

As stated in the sixth post, which you obviously missed. Besides, the problem is sorted!