S2000 hesitation and CEL problem

[Jeff_E]

Hey guys, I'm new to the whole s2000 scene and I'm still learning. Recently bought a S2000 and it needs some work done to it. Let me start off with the hesitation problem. I've read a couple of forums and threads (Most of them from s2ki) saying that it could be due to one of the following:

-Throttle body
-Fuel pump
-Map sensor
-Loose throttle cable
-Ignition coil
-Plugs
-Wires
-Dirty intake

I replace my dirty intake already and the hesitation was gone for a day and then It came back again today. It only hesitates in low rpms. around 2500-3500? A lot of the guys from s2ki said it could be the map sensor. I'm not too sure which one would it be. If someone already encounter this problem before and have fixed it would you mind sharing how you fixed yours? Help is really much appreciated.

Next will be the check engine light being on all the time. Got it check 3 times and it didn't throw any codes at all!!! Will this be connected to the first problem?

Thanks!
-Jeff

[natty54]

dont have a s2000 but from what I know...

I would deff have a look at a plug and see what condition it is in. and if you dont know when they were last replaced change them.

look inside the TB see if there is any carbon build up - could be causing it to stick

the check engine light will more than likely tell you whats up so scan it, post up the codes and go from there

[Jeff_E]

Originally posted by natty54
dont have a s2000 but from what I know...

"I would deff have a look at a plug and see what condition it is in. and if you dont know when they were last replaced change them.

look inside the TB see if there is any carbon build up - could be causing it to stick"

will definitely look into this over the weekend.

"the check engine light will more than likely tell you whats up so scan it, post up the codes and go from there"

i got it scanned 3 times and it didn't show any codes at all.

[eglove]

change the spark plugs, mine had that and as soon as I swapped it was less prone

[Jeff_E]

Originally posted by eglove
change the spark plugs, mine had that and as soon as I swapped it was less prone

thanks for the input! will do plugs this weekend and probably the map sensor too. I will update this thread on what will be the progress!

Thanks!

[jaylo]

Originally posted by Jeff_E


thanks for the input! will do plugs this weekend and probably the map sensor too. I will update this thread on what will be the progress!

Thanks!

I got a set of OEM NGK Spark Plugs brand new from my previous S2000. I will post it up in Kijiji and send you the link

I got miscellaneous OEM parts too like washers and drain plugs when you change transmission and differential fluid

[Jeff_E]

Originally posted by jaylo


I got a set of OEM NGK Spark Plugs brand new from my previous S2000. I will post it up in Kijiji and send you the link

I got miscellaneous OEM parts too like washers and drain plugs when you change transmission and differential fluid

sweet! please send me the link if you can. Right now I'm not sure if I'm going OEM NGKs or Go Iridium. but send me the stuffs that you have and I will grab a couple. Thanks!

[jaylo]

Here you go

http://calgary.kijiji.ca/c-cars-vehi...AdIdZ417235454

[xviper]

Originally posted by Jeff_E

-Throttle body
-Fuel pump
-Map sensor
-Loose throttle cable
-Ignition coil
-Plugs
-Wires
-Dirty intake

Next will be the check engine light being on all the time. Got it check 3 times and it didn't throw any codes at all!!!

Not likely fuel pump. If it was it would run crappy at high rpm when fuel demand is highest.
If you have a loose throttle cable, it's not likely causing your problem. A loose cable would simply give you more free play at the top of the gas pedal.
The S2000 does not have any plug wires.

If the CEL is on all the time, it must have at least one code. How did you "check" it?
Does your MAP sensor have the ziptie mod? Have you ever cleaned your injectors?

What do you mean you "replaced your dirty intake already"? What exactly did you replace? Only your air filter gets "replaced". The rest of the intake doesn't normally get replaced unless you bought a CAI.

How about telling us what year and mileage on the car? Mods? Just saying you recently bought an S2000 doesn't mean much.

[Jeff_E]

Originally posted by xviper

Not likely fuel pump. If it was it would run crappy at high rpm when fuel demand is highest.
If you have a loose throttle cable, it's not likely causing your problem. A loose cable would simply give you more free play at the top of the gas pedal.
The S2000 does not have any plug wires.

If the CEL is on all the time, it must have at least one code. How did you "check" it?
Does your MAP sensor have the ziptie mod? Have you ever cleaned your injectors?

What do you mean you "replaced your dirty intake already"? What exactly did you replace? Only your air filter gets "replaced". The rest of the intake doesn't normally get replaced unless you bought a CAI.

How about telling us what year and mileage on the car? Mods? Just saying you recently bought an S2000 doesn't mean much.

yes i got it check 3 times. 1 from autovalue, 1 from parts source and 1 from work. same thing. didn't throw any codes at all. Sorry, I mean the air filter not the whole intake. My bad. It's 2001 roughly 149xxx. it's bone stock. aside from the K&N air filter that was dirty so I replaced that one.

As what I've said, I'm still learning. I don't have that much idea about s2000s yet.

Thanks!

[xviper]

Originally posted by Jeff_E


yes i got it check 3 times. 1 from autovalue, 1 from parts source and 1 from work. same thing. didn't throw any codes at all. Sorry, I mean the air filter not the whole intake. My bad. It's 2001 roughly 149xxx. it's bone stock. aside from the K&N air filter that was dirty so I replaced that one.

As what I've said, I'm still learning. I don't have that much idea about s2000s yet.

Thanks!

If you didn't "throw any codes", then your CEL cannot be on. Are you sure it's the CEL that's on? Is it the symbol of the little engine? Or is it the "MAINT. REQUIRED" light. If the CEL (aka MIL .. Malfunction Indicator Light) is on, there has to be a code. Did they put a scanner into the OBD II port?
If it's the maintenance light, it's just a mileage counter. Just reset it. Nobody goes by that thing anyway.

Did you know that a K&N filter is supposed to be cleaned and re-oiled?
At that year and mileage, the car likely needs new plugs and an injector cleaning with concentrated injector cleaner. It's probably the original MAP sensor and no previous owner has done the ziptie mod or taken it to Honda to get it done. The early S2000 MAP sensor have been known to be a bit of a problem area. Either the sensor itself needs to be replaced or at the very least, the wiring harness going to it needs to be securely fastened with a ziptie. At this stage of the car's age, you are well advised to remove the MAP sensor and clean the air passage way with WD-40, then dry it out with low pressure compressed air. Put the sensor back on and make sure the contacts in the harness are clean, plug it back in and secure it with a ziptie. The vibration of the motor causes the contacts to move around, not allowing a good signal to get through. This generally causes hesitation and missing.
Then there's the primary (and secondary) O2 sensor. These could be getting "tired". The car may be bone stock now, but do you know for sure it's always been that way? Certain mods can lead to degradation and premature death of O2 sensors.

[Jeff_E]

Originally posted by xviper

If you didn't "throw any codes", then your CEL cannot be on. Are you sure it's the CEL that's on? Is it the symbol of the little engine? Or is it the "MAINT. REQUIRED" light. If the CEL (aka MIL .. Malfunction Indicator Light) is on, there has to be a code. Did they put a scanner into the OBD II port?
If it's the maintenance light, it's just a mileage counter. Just reset it. Nobody goes by that thing anyway.

Did you know that a K&N filter is supposed to be cleaned and re-oiled?
At that year and mileage, the car likely needs new plugs and an injector cleaning with concentrated injector cleaner. It's probably the original MAP sensor and no previous owner has done the ziptie mod or taken it to Honda to get it done. The early S2000 MAP sensor have been known to be a bit of a problem area. Either the sensor itself needs to be replaced or at the very least, the wiring harness going to it needs to be securely fastened with a ziptie. At this stage of the car's age, you are well advised to remove the MAP sensor and clean the air passage way with WD-40, then dry it out with low pressure compressed air. Put the sensor back on and make sure the contacts in the harness are clean, plug it back in and secure it with a ziptie. The vibration of the motor causes the contacts to move around, not allowing a good signal to get through. This generally causes hesitation and missing.
Then there's the primary (and secondary) O2 sensor. These could be getting "tired". The car may be bone stock now, but do you know for sure it's always been that way? Certain mods can lead to degradation and premature death of O2 sensors.

-Yes it is the CEL and not the Maint. Req. I know the difference of the two. And yes it is weird because it didn't show any code/s 3 times.

-Yes i know the K&Ns needed to be cleaned and re-oil. I replaced mine because I needed something to put in there while I am cleaning the K&N.

-I will do the plugs tomorrow and the map sensor on the weekend. Will follow your advice about cleaning them and doing the "zip tie" method

-I will have to check the O2 sensors just to make sure.

Thanks for the info. I will definitely follow your advice! Thanks a lot!

[xviper]

Can you be sure you have a stock ECU. The only time I've seen the CEL on and no codes is when an aftermarket AEM ECU is used.

[Jeff_E]

Originally posted by xviper
Can you be sure you have a stock ECU. The only time I've seen the CEL on and no codes is when an aftermarket AEM ECU is used.

I will check the whole car this weekend. I'm pretty sure it is stock. The car has never been swapped or anything. I will update this thread as I go.

[Jeff_E]

*Update!

Maintenance stuff:

-Plugs were changed
-Fresh Oil Change
-Fresh Diff. Fluid
-Cleaned the map sensor.
-ECU reset

Unfortunately "HESITATION" is still present on the 2500-3500 rpm mark. =(

Ordered a new Map Sensor from Honda and will be here Monday. I hope this will fix the problem.

[sneek]

Originally posted by xviper
Can you be sure you have a stock ECU. The only time I've seen the CEL on and no codes is when an aftermarket AEM ECU is used.

I think you're onto something. Perhaps you need to change the fuse for the ECU or maybe the ECU is bad?

[Kloubek]

If there is an ECU fuse that was blown, you'd notice a lot more issues than hesitation. While possible the ECU is bad, I find that somewhat unlikely. The fact it is tripping the light without throwing a code is really really weird - I've *never* seen that....

[Jeff_E]

Originally posted by Kloubek
If there is an ECU fuse that was blown, you'd notice a lot more issues than hesitation. While possible the ECU is bad, I find that somewhat unlikely. The fact it is tripping the light without throwing a code is really really weird - I've *never* seen that....

Will change the fuse tomorrow and see if that will fix it. Yeah it is weird. Got it checked "3 times" and didn't throw any codes out. I will get it check sometime next week for the fourth time and hopefully it will throw something out.

PS. Thanks for the mod who changed my title to a better one.

[Dim_Sum]

Have you checked history stored codes?

[Jeff_E]

Originally posted by Dim_Sum
Have you checked history stored codes?

hmmmm, how do you do that? Sorry if that sounded like a dumb question. I'm a noob...