[rwhiting]

I seem to have a miss or a jerk between 2000 and 3000 rpm and sometimes it doesn't start as easy as it used too. I have no cel. I did have a p0125 and I cleaned my 02 sensors and it went away. I gutted my pre-cats 2 years ago and put spacers on my 02 sensors. After the problem began I have replaced the spark plugs and coil packs but still have the same problem. I have a scanner and I am not sure what to look for. I have no codes and no pending codes. I also pulled the map sensor and cleaned it. I would appreciate any suggestions or direction.

 

[Cap Weir]

Few things come to Mind..

125 then you cleaned the Sensors.. The Sensors are not cleanable.. and doing so can damage them..
Gutted Pre-Cats.. then Installed Spacers?.. as in Anti-Fowler Spacers behind the O2 Sensors?.. WAY NO BUENO if this is what you did..

Need the Spacers Question answered.. then we can proceed from there..

Cap

 

[pturley]

I seem to have a miss or a jerk between 2000 and 3000 rpm and sometimes it doesn't start as easy as it used too. I have no cel. I did have a p0125 and I cleaned my 02 sensors and it went away. I gutted my pre-cats 2 years ago and put spacers on my 02 sensors. After the problem began I have replaced the spark plugs and coil packs but still have the same problem. I have a scanner and I am not sure what to look for. I have no codes and no pending codes. I also pulled the map sensor and cleaned it. I would appreciate any suggestions or direction.

Maybe ask the Miss and the Jerk to trade places, and see if their hesitance goes away?

 

[Russell55]

Maybe ask the Miss and the Jerk to trade places, and see if their hesitance goes away?

Well, that realy helps.

 

[spydertoph]

Bahahah, You'll fit right in here.

Maybe ask the Miss and the Jerk to trade places, and see if their hesitance goes away?

 

[rwhiting]

Bahahah, You'll fit right in here.

I was only looking for some help. I did clean my 02 sensors they had carbon build up on them I used seafoam I have done this on several vehicles it doesn't hurt the sensors and most of the time it works. I removed the anti-fowlers today even though they have been on the car for over two years. The car has a miss and I can't find it. I have a scanner I am not sure what the fuel trim should be. My 02 sensors change between 0.000 to .45000 and the maf sensor changes with the rpm. I though that somebody on here might know the direction I should look. I have no cel I changed the coil packs and the plugs.

 

[OldMan]

Post Deleted

 

[rwhiting]

Perhaps you have a dirty/clogged fuel injector.

What prompted you to install anti-foulers in the first place?
I'm thinking we may be dealing with a problem of long standing.

I was thinking that was a possibility I used two cans of seafoam in the tank, I am not sure how to check the injectors

 

[Cap Weir]

The 'Anti-Fowlers' are used to Isolate the O2 Sensor, from fast changes in o2 concentration.. this is not a good thing when used in a fueling Loop.. it's Fine ( and Desirable ) in a Cat Sensor loop..

Need to get the Car running for a few drive cycles to get the fuel trims settled..

There are 4 fuel trims..

2 Long , 2 Short.. they are for bank one, and bank two..

Idealally you want the LTFT for bank one and two to be ~+5.. that is where the Stock Spyder Air box runs..

The STFT's should be less than +-5 for both Bank one and Bank two..

If the Long term Fuel Trims are different from each other by more than 5, you have an Injector problem.. or an Intake leak..

By Removing the 'Spacers' the fuel trims will now react faster, and the STFT's can do more work for you..

Ideally the STFT's will be the same Bank one and Bank two.. ( ~2 from each other )..

Let about 3 or so Drive Cycles go by, then look at the Fuel Trims with the Engine Idling at 2K in the parking lot.. I expect to see

LTFTB1 +8
LTFTB2 +8
STFTB1 +2
STFTB2 +2

Or something like that.. with the Speed Constant.. and while driving on a steady load.. should be about the same..

If the Trims are out in the Double Digits ( >10 ) then something is amis.. also the long trims should be close to each other.. and the Short Trims should be close to each other..

Post what you find..

Cap

 

[rwhiting]

The 'Anti-Fowlers' are used to Isolate the O2 Sensor, from fast changes in o2 concentration.. this is not a good thing when used in a fueling Loop.. it's Fine ( and Desirable ) in a Cat Sensor loop..

Need to get the Car running for a few drive cycles to get the fuel trims settled..

There are 4 fuel trims..

2 Long , 2 Short.. they are for bank one, and bank two..

Idealally you want the LTFT for bank one and two to be ~+5.. that is where the Stock Spyder Air box runs..

The STFT's should be less than +-5 for both Bank one and Bank two..

If the Long term Fuel Trims are different from each other by more than 5, you have an Injector problem.. or an Intake leak..

By Removing the 'Spacers' the fuel trims will now react faster, and the STFT's can do more work for you..

Ideally the STFT's will be the same Bank one and Bank two.. ( ~2 from each other )..

Let about 3 or so Drive Cycles go by, then look at the Fuel Trims with the Engine Idling at 2K in the parking lot.. I expect to see

LTFTB1 +8
LTFTB2 +8
STFTB1 +2
STFTB2 +2

Or something like that.. with the Speed Constant.. and while driving on a steady load.. should be about the same..

If the Trims are out in the Double Digits ( >10 ) then something is amis.. also the long trims should be close to each other.. and the Short Trims should be close to each other..

Post what you find..

Cap

Thanks for your answer this is the kind of help I was hoping to find. I have not put it through much of a drive cycle yet. Here is some of my readings right now. This is at idle

tps 12.5
rpm 1300
maf 4.16
st ftrm1 -7.7
lt ftrm1 4.6
st ftrm2 -7.7
lt ftmr2 7.6

 

[Cap Weir]

These numbers look good.. have a friend ride with you as you do a steady run at 2 to 3 K RPM..

Both Short term numbers are the same ( -7.7 )

Long terms of 4 and 7 is not crazy by any means..

I was thinking the Jerking might be a trim not responding because of the 'Spacer'.. We'll see if that goes away or not..

See if you can keep it 'Jerking' and look at the trim numbers.. what are they doing?..

COULD be a PCV valve hanging..

Cap

 

[rwhiting]

These numbers look good.. have a friend ride with you as you do a steady run at 2 to 3 K RPM..

Both Short term numbers are the same ( -7.7 )

Long terms of 4 and 7 is not crazy by any means..

I was thinking the Jerking might be a trim not responding because of the 'Spacer'.. We'll see if that goes away or not..

See if you can keep it 'Jerking' and look at the trim numbers.. what are they doing?..

COULD be a PCV valve hanging..

Cap

okay I will give this a try tomorrow. Is there a pcv valve on an 01? I can't seem to locate it.
Thanks for all your help

 

[Cap Weir]

Screwed into the Cam Cover next to the Air Box..

Cap

 

[rwhiting]

Screwed into the Cam Cover next to the Air Box..

Cap

I cleaned the cpv valve. I drove it today in 5th gear at 2500 rpm

St ftrm 1 -21

lt ftrm 1 19

st ftrm 2 -21

lt ftrm 2 18

 

[T-bone]

000000000

 

[Cap Weir]

in this shot, the Short term and the Long Terms are Opposite of each other and past 15.. So they are fighting..

drive it for a while to let the trims re-develop, and see if they settle back below 10

The bank one and bank two trims are about the same, so it's not an injector problem..

Cap

 

[OldMan]

Post Deleted

 

[Cap Weir]

A Battery reset would have been good right after the Cleaning. that would have eliminated the High Long Term and High Short term Trims.. but as soon as the Switch was turned off from the Last Trip, the Trims will add to each other, and with trims out that High, and in the opposite direction, the net result will be close to zero.. and that is where the Bat Disconnect would have brought the Trims to anyway.. so you only add to the Process by about one or two drive cycles by not reseting the ECU..

So at this point, it's not worth it.. They are on the way to being stabilized now..

Cap

 

[rwhiting]

A Battery reset would have been good right after the Cleaning. that would have eliminated the High Long Term and High Short term Trims.. but as soon as the Switch was turned off from the Last Trip, the Trims will add to each other, and with trims out that High, and in the opposite direction, the net result will be close to zero.. and that is where the Bat Disconnect would have brought the Trims to anyway.. so you only add to the Process by about one or two drive cycles by not reseting the ECU..

So at this point, it's not worth it.. They are on the way to being stabilized now..

Cap

okay I will watch it through several drive cycles and keep you informed on the situation.
Thanks for everything

 

[rwhiting]

okay I will watch it through several drive cycles and keep you informed on the situation.
Thanks for everything

today at idle
st ftrm1 -14.5
lt ftrm1 8.5

st ftrm2 -11.5
lt ftrm2 12.5

This morning i had a miss at 1500 rpm and i was able to hold it there for a few seconds. I got a pending miss fire
P0303. Any thoughts? Could it possibly be the TPS or CPS?
It seems like it has no power if I am going slow, put it in a high gear and floor it it just bogs down, but on the highway at 60 it has plenty of power