nnac7270

I just picked up a 1993 Del Sol Si for cheap. It has 4 cel 4 CKP - crank position sensor, 14 IAC (EACV) - idle air control valve, 19 Automatic transmission lockup control valve (Car is a 5 speed I'm guessing it was swapped from an auto or for some reason has a auto ECU I read up on converting the ECU to a manual i will eventually get around to it), Last code is 22 VTEC pressure valve.
Since i got it i changed the spark plugs to new NGK plugs All did a compression test all cylinders reading a healthy 195 PSI. Changed gear oil and just ran some seafoam and fuel system cleaner through it. When starting cold the engine rpms jump up and down (are higher then usual). Once warm it settles down like it should but occasionally surges when its warm. When its in gear and rolling with no throttle or a little throttle (rpm around 1500) it will sometimes buck and jump like its about to stall but it doesn't (feels like I'm in 3rd gear) But as soon as i give it a decent amount of gas it drives pretty normal. It does the same in 2nd so on (i don't have it on the road yet so i can't drive past a couple gears. Any suggestions as to what my issue could be? I checked for air leaks but i couldn't find any. Could ecu being an automatic ecu cause the bucking problem? As far as the code 22 Vtec pressure valve I'm going to change the oil and go from there. Im new to this forum so if i said or did anything wrong please let me know. Thanks.

tony_2018

Does it have a FITV?

nnac7270

Im honestly not sure. This is the idle air control valve it has though

Ill look into how to find out if it has the FITV.

Mac2118

iTrader: (1)

the FITV "should" be on the bottom of the TB



It sounds like you have a bad vacuum leak also. I had something similar with a vacuum hose that was bad and the idle was high and the car bucked like crazy until I replaced the hose. I'd grab some carb cleaner and lightly spray it around vacuum lines to see if your idle changes.

nnac7270

Thanks for that. No it doesn't have FITV. I was checking for vacuum leaks earlier today i couldn't find anything but ill check again tomorrow.

JarvisW

Also, clean FITV and IAC, then double check mechanical timing and go ahead and reset the tensioner there. I did that and it made a world of difference in my rough idle and occasional bucking feeling.

Then, reset the idle following the FSM or from the FAQ here. And check ignition timing.

good luck!

nnac7270

Im more leaning to timing from the distubtror or maybe a mix of both problems. The previous owner said he replaced the distubtror (he called it a carburetor lmao) so he probably doesn't really have much of and idea of what he is doing. I will check and adjust the distubtror timing tomorrow and hope that helps.

JarvisW

double check the belt tension too tho. I was surprised to see it wasnt set right on mine.

nnac7270

Ill be sure to do so.

stocker2shocker91

I would swap that ecu out for the correct one before you get to involved in mechanical troubleshooting. If the ecu is looking for parameters that are not there it can cause all kinds of issues.

what engine is currently in it?

JarvisW

Oh, I didnt see the post above mine that said there was no FITV..

Yeah, update the OP to include what engine its got.

Under the head to the side of the manifold on the front of the engine.

nnac7270

It has the d16z6

nnac7270

I was looking to do this Civic EG :: View topic - How to convert your Auto P28 to Manual instead of buying a new ecu.

JarvisW

then it should have an FITV. check to see under the Throttle Body. should have 2 hoses going to it.

What ECU does it have besides an auto one?

Another thing to check is be sure the IAC has the right plug to it. There is another one that can fit there, but it wont run right (don't think its it, but just checking)

JarvisW

The proper ECU will throw the auto code, but the other ones are the same on both, so those are different problems.

Like above, what ECU, so we know what we are goin with.

nnac7270

Oh really I'm going to check over everything again tomorrow morning. I was really just guessing I just got the car Sunday night. I'll get back about it tomorrow. Thanks for all the help so far.

JarvisW

K. double ck the engine IS a z6 and the ECU, then we can go from there.

Good luck

tony_2018

Holy ****** ****...before responding to anyone's replies just confirm what you got and replace the ecu with a 5spd p28....or convert it to a 5spd. Whichever fits your budget and capacitiy.

nnac7270

Okay so heres the deal. I apologize for giving false information above. It does have FITV and it has a D16Y1 engine. I did the ECU auto to manual conversion successfully code 19 is off. I then took off the throttle body cleaned the FITV made sure the coolant hoses weren't clogged also cleaned the IACV again and put it back on. It starts and doesn't seem to have the idle problems anymore when cold. But it still bucks and idle surges when clutch out rolling in first gear and second like I'm going to stall but the rpms are at 1500. Here are the new codes i am displaying 6,10,14,22.

Former User

Reset the ECU to see if all the codes return.

From Australia?
https://en.wikipedia.org/wiki/Honda_D_engine#D16Y1

nnac7270

All codes written above return

Former User

Check whether the IACV, ECT, IAT, and VTEC solenoid are unplugged.

If not, post pictures of each sensor connector above clearly showing the sensor and sensor connector wires.

Where did you get a D16Y1 engine? Are you from Australia?

nnac7270

The vtech solenoid plug is all corroded and the wires are frayed and cut. I'll be replacing that. I have no idea where lol I just bought the car on Sunday

Former User

VTEC not VTECH

What about the other sensors? Post the requested pictures.

Are you misreading a D16Y7 block code as D16Y1? Post a picture.

What's the engine head code? Post a picture.

https://honda-tech.com/honda-civic-d.../#post48684945

nnac7270

No I'm not misreading it. I will post all pictures tomorrow when its daylight again. I was able to obtain the plug for the vtec solenoid today. After installing it and resetting the ECU again the only code that came back is 14. Now what seems to be happening is when the engine is colder it gets stuck at 1500 rpm until i give it more gas then it is fine above or below 1500. When the engine is at full operating temperature it doesn't do it. Video will be posted soon.