The R has started to jerk a bit. When it's cold it seems to work fine, but when it's fully warmed up it's starts to jerk.

It only jerks below 4000rpm. Above is fine.

In vtec I can't go WOT without it starting to jerk, but I can go vtec with say less than 90% throttle.

With little load, say less than 10% throttle, it seems to run fine regardless.

I've checked the spark plugs and wires, distributor and rotor. I've also changed the IACV to no avail. Fuel filter and was changed about a year ago.

What might be wrong?

It started to do this after a very cold period here (-20C). Unfortunately I had to start her up a few times, and after a few days the jerking started. Don't know if it has anything to do with it though....



Modified by Pompiuses at 8:55 AM 1/12/2006

 

Could it be a faulty ECT (engine coolant temperature) censor?

 

Map or TPS?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pompiuses &raquo;</TD></TR><TR><TD CLASS="quote">The R has started to jerk a bit. When it's cold it seems to work fine, but when it's fully warmed up it's starts to jerk.</TD></TR></TABLE>

 

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


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No informative response? You dont see that too often from you!

 

I think Ken made a funny. He took the original posters car jerk and made it into a joke by mimicking a hand to ***** jerking motion.

haha!

&lt;--Stiff

 

Come on you posers... if you can't answer the guy's question then there is no point for you to post on here at all.

My car was doing the same thing and then I changed the oil and it stopped doing it. My oil level was low but not below the lowest point on the oil dip stick... weird.

Keep in mind that I drive a k-series car, so I don't know if the same symptom/fix would apply to a b-series car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ff_terror &raquo;</TD></TR><TR><TD CLASS="quote">Come on you posers... if you can't answer the guy's question then there is no point for you to post on here at all. </TD></TR></TABLE>

Some people have no sense of humor.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ff_terror &raquo;</TD></TR><TR><TD CLASS="quote">My car was doing the same thing and then I changed the oil and it stopped doing it. My oil level was low but not below the lowest point on the oil dip stick... weird.</TD></TR></TABLE>

If it's not below the lowest point on the oil dip stick, the level shouldn't cause jerking. If there was something wrong with the oil, that's a different story.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nsxtasy &raquo;</TD></TR><TR><TD CLASS="quote">If it's not below the lowest point on the oil dip stick, the level shouldn't cause jerking. If there was something wrong with the oil, that's a different story.
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FWIW my gf's little brother had the same occurrence in his swapped EG. The car would jerk violently at low RPM's. He replace his motor mounts and was good to go. His front torque mounts were shredded. As far as an R goes I've never heard of this occurrence. Let us know how it works out.

Ken still made a funny

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ff_terror &raquo;</TD></TR><TR><TD CLASS="quote">Come on you posers... if you can't answer the guy's question then there is no point for you to post on here at all.
</TD></TR></TABLE>

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

Some people have no sense of humor.

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Yeah who didn't look at the post and laugh. I know i did

 

ECT turned out fine....

I've also tried testing the IAT (intake air temp) sensor by measuring resistance between the connectors. The Honda manual states it should be betwen 0.4-4.0 kilo ohm. Mine measured 6.1 kilo ohm.

It was measured outside in only 2 degrees celsius temperature. Might that affect the result?

Anyone care to comment?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Opie &raquo;</TD></TR><TR><TD CLASS="quote">FWIW my gf's little brother had the same occurrence in his swapped EG. The car would jerk violently at low RPM's. He replace his motor mounts and was good to go. His front torque mounts were shredded. As far as an R goes I've never heard of this occurrence. Let us know how it works out.</TD></TR></TABLE>

same thing happened with my car, turns out my motor mount was totally broken (on my EM1). 'course, it always jerked, just because of momentum and the engine moving around, it was unrelated to engine temperature

 

Measured the IAT sensor after a short drive. Now it measured 1.7 kilo ohm. Which means it is within spec.

That leaves only the lamda sensor to test, as I've testet just about everything else.

If the lamda turns out fine as well I really have no clue what's wrong . Possibly the MAP or TPS, but I doubt it.

 

Changed the lamda sensor today (there's only 1 lamda on euro ITRs), but to no avail . After about 10 minutes of driving the car starts jerking pretty bad. It runs completely fine before that.

I really have no clue to what's wrong .

Looks like I have to face defeat and take it to the dealer.

 

How is your ignition system?

When was the last time you replaced the distributor cap, rotor button, spark plug wires, spark plugs, and possibly ignitor?

This can cause ignition misfire or stuttering, which can feel like the car is stumbling.

Usually this will also make the fuel burn inefficiently and cause plugs to foul or look really rich.

Not to mention it may happen at a certain rpm window or throttle position i.e.: at 3500 to 4500 rpm at 40% throttle..... or only at WOT, etc.....

 

Found out what's wrong ; It's leaking coolant.

It's steadily decreasing coolant from the expansion tank each time I drive the car. The last week level has gone down by about 2cm.

I took the IM (intake manifold) off a few weeks ago, and I think it leaks from the IM into cylinder #4. I reused the stock IM gasket, so perhaps that was a bad idea?

But is there a way to find out for sure that it leaks from the IM into cylinder #4? Preassure test or something?

#4 spark plug look fine though.

 

I wouldn't have thought of that!

You didn't throw any codes, did you? And the #4 plug looked the same as #1? Hmm.

That little amount of coolant shouldn't cause a problem. If you can smell sweet coolant in your exhaust, that'd indicate a problem. But if you're really leaking coolant, maybe you should fix that too

My guess is that you have a weak spark. New coil/distributor might help. Do you have a friend's dizzy that you can borrow for a half day to test it?

Only difference about the cold, is maybe the coil works better when it is frozen, or the rich fuel mixture from being cold helps it fire better. Electronics have a lower resistance when they're cold, so that would be my guess.

Good luck....

 

It turned out that it wasn't coolant that was leaking after all.

It was actually a tiny bit of water inside the distributor cap that caused it all. It was so little that it was hard to notice , but obviously enough for a flashover.

Just cleaned it up and the car runs like a champ again. It's silly that something that simple has kept my car out of action for almost a month now.

 

Good work detective. I was going to suggest that you look at your idle RPM and adjust your idle accordingly. Another one would be that the screen is plugged up on your IACV. Another could have been that your throttle cable was out of adjustment.

At any rate good work. Where did you find the water hiding in the distributor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Haleiwa-Brando &raquo;</TD></TR><TR><TD CLASS="quote">At any rate good work. Where did you find the water hiding in the distributor?</TD></TR></TABLE>

It was in the little indentation in the middle of the cap. Made it kinda hard to detect.