Help car jerks once at 2300 rpm.

Today while I was driving I noticed that my car would jerk once when I was accelerating. It always jerks right at 2300 rpm or so and after that it would be fine. Just one small jolt. It will also jerk/jump when in neutral. Its a manual car so i dont think its the clutch and transmission or is it the clutch thats causing it? Also just yesterday my car overheated cause the hose to the idle control broke. I think it was the oem hose too... But anyways it overheated. Could that of damaged the spark plugs? But like other than the small jerk everything else is mostly fine. I replaced the hose already and it runs cool again. But that small jerk is annoying.

Vid of issue? You mention an idle control, so I assume this is a fuel injected car? Is it when you're accelerating aggressively, or just puttering along? If you hold it at 2300 what happens?

Yes it is a fuel injected car. Just whenever it gets to that specific rpm it jumps up a bit then returns to a normal climb. On second thought could it be the egr opening? Because before it would only do that on cold starts lasted less then a minute and when it was warm it would go away. ill try to get it on video.

Ok it just Fixed it self. The jump went away for now. Thanks

I missed the overheat part. Make sure coolant is full and you bleed it using the bleeder on the thermostat housing. You may also have to release air trapped in the IACV buy loosening the coolant line.

I think its an ecu problem? It comes back sometimes and ill just have to turn my car off and back on and it'll go away... Also how do I bleed it? Like which hose do I release cause there's 2 but they are both below the idle control.

Could that also be why my car has a really crap idle?

[QUOTE=frastydragon;1220878]Could that also be why my car has a really crap idle?[/


There is a bleeder screw on the thermostat housing and its in the manual how to properly bleed it.

The IACV i just loosen the clamps and when you start to wiggle the hoses off youll start hearing air escape. Needle nose pliers helps on the hose not the nipples of the IACV.

Here is it acting up. Happens like 5-10% of the time. I use it to deliver food. Everytime it acts up i have to shut the engine off and turn it back on and it'll go away. Its a manu. At 1st gear there is a big jerk/jump. At 2nd gear there is a smaller one. And 3rd is lesser. Haven't tried 4th or 5th yet. I can't really hold the rpm stable at 1st and 2nd. At 3 when I held it, it would be stumbling. Acting like there's no spark? Or is it no fuel? Timing problem? Idek anymore.

Here in the video the beginning is at 2nd gear. You can't really notice the camera shake but it jumps a few times when I get to the 2300ish rpm. Near the end you'll see me hold it at 3rd gear and it just shudders until I give it more gas and it'll pass the trap point.




https://youtu.be/uwbHMEfD9Ls

Ok first thing is take the distributor cap off,rotor button and the dust shield and see what the inside of the distributor looks like. I kinda suspect the vacuum advance is messed up in there. Look inside the cap at the posts and look the rotor over as well. You can leave the wires on the cap or mark them well when you remove them.

The other things you could try is new NGK plain spark plugs and a new fuel filter.

I dont really like the knocking noise its making when it doing it

Another simple idea is when your cruising steady wiggle the ignition key and see if it does it. The ignition switch contacts may have worn out have worn.

Does it only do it at night?

Clearly, your car is haunted. Are you getting a CEL? I'd be looking for a bad sensor myself, but I can't say what's going on exactly.

Hello, I am new here...
Definitely won’t be part of the solution but I am on the same boat with you OP. I have a 1989 Se-i and as I’m driving, it jumps at 2k or 2.2k rpm. Mostly on 1,2,3 and 4. Haven’t really noticed or tried to look at it on last year but yes it does happen. Both day and night. I was thinking it could be a misfire but I’m not very educated when it comes to automotive mechanics.

Ill have to try that ignition wiggle. It happens anytime of the day. Whenever it wants to act up. And I havent had a CEL. But I know I should be having one. Where is it anyways?

I feel like it's the spark cutting out to make it jump. Only explanation I can think of. Some maybe something wrong with the advance? Idk

https://www.3geez.com/forum/newreply...1397&noquote=1

the ECU is under the drivers seat.

Ecu has 9 blinks. Code says the location is the CYP sensor so I think the cause could be Wiring or the sensor. So I hope its just the wiring. Where is it located?

Quote:

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Originally Posted by frastydragon

Ecu has 9 blinks. Code says the location is the CYP sensor so I think the cause could be Wiring or the sensor. So I hope its just the wiring. Where is it located?

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I believe thats inside the distributor and I dont think its replaceable, well unavailable part.

The problem hasnt gotten worse yet so should i just keep it on or do a replacement or swap? Cause it looks like the dizzy has been replaced before.

You might look into some of the dizzy swap options, Im not an EFI guy so idk what that entails, but theres some guides around here and Shane had an h22(I think) dizzy he was selling