Hello everybody.Well i am having a serious problem with my car since i bought it 6 months ago.The car seems hesitant/shaky taking off - particularly noticeable in 1st/2nd/3rd gears - Now I know she runs in 12Valve mode at low revs but even with this I think it should be smoother/stronger taking off...

Things changed and verified with no result:
Cam timing is aligned to marks.
Ignition timing is set at 16 degree,
Fuel filter changed,
Valve adjustment done recently.
Checked spark plugs,wires,rotors,and cap.
Ignition coil seems good as the engine doesn't misfire at all,
Ground wires are tight.
New battery and alternator just changed,
cleaned intake manifold,throttle body,and iacv also.

Specs of Car:
Ek3 year 99 D15B 3 STAGE VTEC M/T
4-2-1 manfold
Lightweight flywheel
Sport air filter.
1.90'' exhaust pipe.

Can anyone tell me what is the possible cause of that symptom?

Thanks..

 

anyone experienced this issue?

 

your car is running like crap, has nothing to do with vtec. Deal with the issue as you normally would with a car.."Ground wires being tight" is not sufficient enough. You need to get an actual multimeter/ohm meter and measure the ohms from the ground to the battery ground. Your Ohms value should be about 0 ohms with anything more than that indicating a bad ground at worst and a dirty ground at best. Ignition timing may be a little too advanced.. If you did a valve head swap, then it's possible you need to re-adjust the valve lash and or the timing belt which could be slightly off. Car could also be running rough if your EGR is clogged/dirty and or your IACV is dirty. A dirty IACV can make the car hard to take off from a start and when you're releasing the clutch.

 

Thanks for replying,well,i used ''vtec'' in the title just to mention the type of engine i have.
Tomorrow i'll check both the ground and the egr.The iacv is clean.

 

As for checking 'the ground', I don't want you to check "the ground". I want you to measure and inspect every single electrical ground you can, especially the body of the o2 sensor to the battery ground. My car is a California car which means no salt issues on the roads and when I checked the ohms value of my grounds, I found all of them to be higher than 1 ohm. Cleaned up all the bolts, washers, eyelits (that copper ring that attaches to the wire), blew out the debris from ground point (don't scrape off paint!) measured again and all the ohms levels dropped to 0 ohms with the most significant improvement being the o2 sensor's ground. (The body of the o2 sensor is used in sending its signal to the ECU)

As for IACV, I'd check it again and manually actuate the valve to see if it moves smoothly. I've never worked on the traditional IACV like those found on the '92-95 civics or the '96-'00 D16y5/Y8 engines but I did do it for the '96-'00 D16Y7 engine and I found my valve was completely stuck. Broke it free but still found it wasn't smooth to actuate and that's where the extensive cleaning process began. I knew the IACV was clean when I put it to my ear and manually actuated the valve and could no longer hear what sounded like grinding w/sand. I'm quite aware the design differences between the two IACV but I believe none the less that they in principle work in similar ways. People clean the valves but I don't know if they actually bother to see if they can move the valve by hand.

 

I'll let you know the outcome of the test.As for the iacv,i confirm its in good working condition.

I've also noticed at night the dash light gets dim when driving and when i stop accelerate its much brighter.But this happens only when driving below 3000 rpm.Do you think this issue has any relation with the sluggish power(at low rpm) what i am experiencing.

Thanks.

 

It could be related. Maybe you've got an A/C pulley/Power steering pulley or alternator that is binding up a bit and is about to fail. Maybe you need to charge your battery because a discharged battery could be overloading your ailing alternator. Maybe you should try removing all the spark plugs and cranking the engine over by hand and see how difficult it is to turn.

 

Alright.The alternator has just been changed to rectify the dimming dash light,but in vain.As for the battery just replaced 2 months ago.Its charging correctly..14.5V with engine on and 12.5V with engine shut off.

I'll be back after checking and measuring the ground.
Thanks.

 

i see the problem......
























its a d-series

 

yes it is....but after driving an another stock d15b i noticed then there is a problem with mine.The other d15b is so smooth,it has more response.Mine is very different,for e.g, if i press the gas pedal from stop light to go,i feel something holds power for 2 seconds then it goes suddenly.its lazy to take off.It does that only below 3000 rpm.

 

did you do anything with the electrical grounds like I asked you to? I know that requires work and effort but I think it's a good use of your effort. Also, I hate to ask but do you have any check engine codes?

 

No cel is on.I'll do the procedures you want me to do,but now i am very busy with my work.I forget to mention above that i've also cleaned the injectors,changed fuel pump with no avail.

 

got to take care of that

 

Helo,well yesterday i went to electrician he told me everything is fine,no wire cut,and the ground is doing its job as it should.Now i don't know what to do,the car just does not pull the way it should ...0 up to 3k rpm..then it just takes a second breath and pulls hard...
its like the car hesitates..and accelerates slow, it is hard to notice jerks..or jumps.. its like there is something restricting to let it pull hard right from the beginning 0 - 3k rpm... then it pulls ok...

I think will sell the car.its a headache.

Do you think guys there might a problem with the timing?maybe the mechanic wrongly verified the alignment of the marks.

 

anyone?

 

Maybe ur belts are to tight?

I had a friend once who tighten his ac belt too much that when he started the car it would try to turn off on him and when he would drive on the street and punch it it would start off slow then when it catched to a certain rpm it would go... maybe its that on urs or maybe not

 

They checked the belts,its not too tight.But now before removing the crank pulley,timing belt etc..,i want to know if timing can cause that?

 

anyone experienced that?

 

Maybe you have extremely bad wheel bearings. Go to a moderate sized hill and just see if your car will roll on its own in neutral. I previously owned a civic that had such bad wheel bearings it felt like the emergency brake was pulled.

 

i confirm the bearing is good,no noise,it turns freely.

 

anyone can tell me if a wrong timing can cause hesitation?

 

Check your timing and calibrate the TPS sensor. Running in 12 valve mode is definitely going to make it slower than 16 valve. Unless you have the correct ECU and wiring, it won't be operating correctly. Maybe not the reason why yours is acting the way it is, but still. If you could run Hondata you could set up one of the outputs to actuate the solenoid just off of idle and then just run a P08 map probably.

 

It is the original engine of my car that came from factory,its a Vi.The ecu and wiring correspond to that of my engine.The TPS was checked and it gives the correct voltage value according to manual.I think the problem is within my cam timing...

 

helo everyone, yesterday we have checked the cam timing,its aligned to the respective marks on the back cover.Crank mark is at tdc,and the ignition timing is set at 16 degrees,the distributor is in the middle.So everything is line up correctly.But why is my car still running weird under 3000 rpm?dislike the car now....

 

I subscribed to this thread because my friends EG hatch D16 was doing the same exact thing. I've also been checking timing (ignition and cam), fuel pressure, plugs, wires, cap, rotor and ignition coil. We Seafoamed his car yesterday. Half bottle in tank and other into intake via brake booster vacuum line. Drove all day yesterday, no hesitation. Worth a try. It's only like $10. Will keep you updated if hesitation returns.