D16Y7 sporadicly runs rough/misfire, no code

[RonJ]

I have what sounds like basically the same problem...
My car has a d16y7 and this started with mine a while back.. it has bothered me but not too much because it would only happen like once a month but now it seems to happen like once or twice a week and its driving me crazy

My car is serviced regularly but the distributer and cables are probably the originals, its a 1999, 5 spd, has a y8 intake manifold and dc sports 4-2-1 header. Only 111000 km so im guessing like 65000 mile or so?
I have no clue at what rpm it happens since I dont have a tach, and mine seems to happen at anytime, when the engine is cold or warm.. Mainly at speeds from 60km/h to 100km/h
Heres what happens to me:
I'll be driving along normally when suddenly my car seems to almost studder or as you say feel like the throttle is stuck or its not getting enough fuel.. If i stay at the same amount of gas it wont really do anything but feel like its loosing power or choking, if I let off the gas the speed just drops, and if I hit the gas down to the floor it speeds up but slowly... I have had it before where it will almost looses all power, even if I hit the gas, and then it will jerk back and take off but that hasnt happend for months...
The only code Im throwing is for the 2nd O2 senor ciruit, which I think is just from my header... Other than that the car runs perfect.

Sorry for the novel but I thought I'd say all I had too, I want to figure this out soon!

You have 69K miles on the odometer. Have you ever replaced the spark plugs, distributor cap, or rotor? If not, start by replacing these as well as the plug wires.

What specific CEL code(s) are retrieved? If you reset the ECU by removing the 7.5A BACKUP fuse under the hood for a few minutes, does the CEL code return/repeat?

 

[quick86]

Okay, it FINALLY did it REALLY bad last night...

Driving at normal speed just after leaving the gym, like 25-30mph through town... My foot steady on the gas, and it feels like the motor just cuts out, like I took my foot OFF the gas and is decelerating slowly. If I push down on the gas pedal is jerks for like 1 second, and comes back to life. The weather was very very dry but very cold out.

I'm going to pull my new spark plugs and read them to see if any cylinder is reading lean or rich. I am also going to replace the fuel injectors with a fresh set. I've got about 150 miles out of a half tank of gas...

I'm not ready to replace distributor yet because I do have a severe doubt that it is it. After replacing my fuel filter last year and seeing how nasty condition it was, I am thinking it's a fuel concern and my injectors and rail are in need of a good cleaning...

 

[RonJ]

You should pull off the fuel rail and inspect the injectors before replacing them.

 

[quick86]

You should pull off the fuel rail and inspect the injectors before replacing them.

I'm getting a set off of a low mileage car for $20. Cant hurt.

 

[quick86]

Ran a higher octane fuel and got improved gas mileage, about 2.5mpg better.

i also got new (used, with more than half the miles of mine) fuel injectors. Two of them have cracked pintle caps so I may be rebuilding them before I install them... Either that or just replacing the pintle caps...

 

[RonJ]

Ran a higher octane fuel and got improved gas mileage, about 2.5mpg better.

You should not need to use higher octane gas to get the best gas mileage. This suggests that your ignition timing may not be set to spec.

 

[quick86]

You should not need to use higher octane gas to get the best gas mileage. This suggests that your ignition timing may not be set to spec.

Oooorrr the fuel injectors aren't efficient enough due to their age/wear.. Seen that happen before too... The higher octane is helping it run better even though the injectors are still not operating at full potential/within spec...

 

[whoopnip]

You should not need to use higher octane gas to get the best gas mileage. This suggests that your ignition timing may not be set to spec.

Haven't you told him numerous times to test the ignition timing? How come nobody ever listens to you, Ron J?

 

[RonJ]

...Timing is fine, it has been checked properly.

Haven't you told him numerous times to test the ignition timing?

Well, to be fair, he did say the timing had been checked properly. I just think the symptoms fit with the ignition timing being off a bit.

How come nobody ever listens to you, Ron J?

Because advice is free and sometimes that's exactly what it's worth.

 

[quick86]

I've checked the timing, it's OK - the plugs I replaced showed signs of a lean condition.


A vehicle can run lean with either a lack of fuel and or lower octane fuel.. Running lean would explain why the issue occurs while the engine is cold. Adding a higher octane fuel only reduced the severity of the issue... It didn't fix it 100%

I'll know more when I get the new injectors installed. Tough to find time to do it with the holidays here.

 

[RonJ]

I've checked the timing, it's OK - the plugs I replaced showed signs of a lean condition.


A vehicle can run lean with either a lack of fuel and or lower octane fuel.. Running lean would explain why the issue occurs while the engine is cold. Adding a higher octane fuel only reduced the severity of the issue... It didn't fix it 100%

I'll know more when I get the new injectors installed. Tough to find time to do it with the holidays here.

With respect to your idea about running lean, you also might want to check for low fuel pressure or a faulty FPR/FPR vacuum hose.

 

[quick86]

With respect to your idea about running lean, you also might want to check for low fuel pressure or a faulty FPR/FPR vacuum hose.

Yeah - a buddy of mine has a new FPR he never used and I just have to meet up with him and he's giving it too me for nothing. lol - never have the time to do it!






God I miss working on domestic carb'd motors.

 

[RonJ]

Yeah - a buddy of mine has a new FPR he never used and I just have to meet up with him and he's giving it too me for nothing. lol - never have the time to do it!

If you haven't already replaced the fuel filter, you also might want to do that.

 

[quick86]

If you haven't already replaced the fuel filter, you also might want to do that.

That was the first thing I did after the plugs/wires...

 

[quick86]

I stumbled across a low mileage distributor for cheap, I am going to pick that up and slap it on just to see if it helps also.

 

[knightxrider1]

crossing my fingers hoping you find out what it is. mine is bucking randomly too. no codes.

 

[RonJ]

I stumbled across a low mileage distributor for cheap, I am going to pick that up and slap it on just to see if it helps also.

Is the FPR working properly? What's the fuel pressure with and without the vacuum hose attached to the FPR?

 

[egjdmh22a]

Not 100% true. I have Autolite plug wires on mine, and I have zero spark/ignition issues...

i bought plug wires from autozone for my h22, and the car ran like s**t, misfiring all over the place, i bought some used oem ones a turbo shop and poof car ran perfect again, like ronj says, oem

 

[quick86]

Went to install the new distributor -- took mine off, and grabbed the new one to notice... It's not the same as what I have. My distributor cap was nowhere near able to fit, the dust cover was nowhere near able to fit, the coil was different.... Sooo --- I cleaned mine, noticed a fairly abnormal amount of carbon dust inside my distributor cap. The rotor, which has maybe 10-12k on it already has wear marks dead center where they should be... So we cleaned the cap and the rotor, reinstalled, reset timing, and I let it cool down. Took it for a drive, and didn't do it the entire drive home. Almost home and got a "slow response" code for my primary O2 sensor. The bucking/hesitation began again when I went in to town later.

Cleared the code @ Autozone and went home without a single hesitation.

Also, dead center in my distributor cap, there was this weird wet spot about the diameter of my pinky finger... Not sure WTF it was...




I haven't thrown a fuel pressure gauge on it yet..

 

[RonJ]

Went to install the new distributor -- took mine off, and grabbed the new one to notice... It's not the same as what I have. My distributor cap was nowhere near able to fit, the dust cover was nowhere near able to fit, the coil was different....

Too bad. Based on what you say below and its high mileage, replacing the distributor seems like a very good idea.

Sooo --- I cleaned mine, noticed a fairly abnormal amount of carbon dust inside my distributor cap. The rotor, which has maybe 10-12k on it already has wear marks dead center where they should be... So we cleaned the cap and the rotor, reinstalled, reset timing, and I let it cool down. Took it for a drive, and didn't do it the entire drive home. Almost home and got a "slow response" code for my primary O2 sensor. The bucking/hesitation began again when I went in to town later.

The dust accumulation inside the distributor is a sign that it needs to be replaced. The O2 sensor code hints that this sensor may be causing the engine to run lean intermittently. Did you ever try unplugging the O2 sensor to see whether it prevented the problem?

Also, dead center in my distributor cap, there was this weird wet spot about the diameter of my pinky finger... Not sure WTF it was...

Post a picture.