Standard 1.6 With Running Issues... Help Needed.

[jr4070 0]

I cannot get it to run properly.

It started with a slight misfire..It just dropped revs for a split second every now and then, it gradually got worse, happening more frequently..

Gradually the fault has got worse resulting in intermittent misfires across the range...this has now grown to a huge flat spot with full throttle and the revs hunt at about 3000 revs. It will not go past 3000 for some reason?

The car idles, slightly lumpy like a kind of misfire.. only happens under load or if reved hard.

Over the last 3 months I have changed......(Between each one the fault has remained the same..)
Fuel filter (new)
Fuel Pump (second hand)
Fuel press reg (second hand)
Plug leads (new)
plugs(new)
Dissy Cap (new)
Rotor Arm (new)
AFM (second hand)
Coil pack (second hand)
Ignition amp (second hand)

I then suspected headgasket problem....So off it came. visibly it looked fine, it was changed due to failure back in 2008.
headgasket c/x'd. valves checked for cracks and fluid check of each valve seat c/out..no leaks.

Reassembled.. Fault still there.

The only thing I can think of to do is get new injectors (second hand).. Or have mine cleaned.

Any thoughts would be helpfull‹

[ALEX 98 1 Cars]

Worth while sending the injectors off to get cleaned anyway. Especially if they've never been done as the filters in them will be shot by now.

Made a noticeable difference on my 1.9 I had. Tick over was much smoother afterwards. The service will also find any problems with them.

 

Chances are though its a wiring issue as Injectors rarely fail enough to cause a misfire (Just tend to get poorer over time).

Though saying that My EP3 Civic Type R had an injector go. but it was obvious as there was smoke coming from it, with a blister forming on the side of it.... Took out my ECU too with it as well... wasn't a cheap fix that.

 

Check the signal wire from the dizzy to the ignition module. These seem to be a common fault as the wire breaks down.

Edited July 13, 2015 by ALEX

[jr4070 0]

I have a video of the problem. I just have to work the magic to post it.. In the video https://www.youtube.com/watch?v=2gTsfF0L4xQ you can hear the car pulsing at approx 3000 rev. I move my phone to show the exposed flap in the AFM.
It looks to be as steady as a rock, i forgot to take the resistor cover off to see if the arm was moving on the track but I can take a guess it wasn't. To get the variation in revs with a constant throttle position and a AFM flap not moving hasn't it got to be fuel? Shouldn't the pressure reg maintain a constant pressure regardless of how open or closed the injectors are, i have swapped that and it has remained the same. The pump was tested with the rail disconnected, not under load, no luxury of a connection for a pressure gauge,(I haven't got one anyway)..I changed it ..The thing is the pump that came out had a blue spot (Blue injectors on a 1.6?) and the one that went in had a yellow spot(yellow 1.9 injectors?..just a guess).. What if the pump is a reduced flow compared to the original and the regulator can't do it's job?...Thing is the original pump and newer reg still have the fault..
The injectors went to be cleaned yesterday... That's my next attack.

[scbond 15 1 Cars]

Doubt it's the AFM causing the issue in the video. Easy way to tell would be to operate the flap by hand at a steady RPM...as it leans or richens too much the engine will cut out.

 

Noticed in the video you have a vacuum hose missing from the right side of the intake manifold. That won't help.

[jr4070 0]

Thanks for the ideas guys.. I can't see the vac hose off though. You can see the bolt in the unused clipping point for the oil filler. Its done up so no leaks through there.

[ALEX 98 1 Cars]

Had this before. But can't for life of me remember what it was. All I remeber it was something simple.

Start with, what was the last thing you changed before it started doing it.

[scbond 15 1 Cars]

Might well be the oil filler tower mounting bolt that I saw, as you said. Could only catch a brief glimpse

[boldy205 75]

Id be putting a new coil on just for peace of mind.

Usually if its under load its on the H/T circuit.

[jr4070 0]

So the injectors came back...they had a low flow rate and erratic spray pattern. They now are back to 100%.

 

Now......it starts fine.. as it warms up it gets worse..again,,,,, Under acceleration it sometimes spits back into the intake with a pop. But it will slowly accelerate up the range.

 

I have a spare temp sensor. I plugged that in and checked if the symptoms persisted when I placed it into boiling water..They did.

 

I have re- checked the belt timings (on the timing holes ) all appears bang on..

 

It has a new pattern part dizzy cap on.. I'm going to try going back to the original ,, It has got worse as I have put on new items... .

[ALEX 98 1 Cars]

Check the wiring to the AFM and the throttle switch is working.