[Eric]

Sorry for the Delay…..

The Main Issue was with the MAF.
This caused codes 181 and 186. Replaced MAF. Codes gone!
Power came back considerably on acceleration and gas mileage improved.

The other issue was with the IAC. Replaced and code 412 was gone.

Only code remaining is 538, so I will probe further but for now , car runs great! NO check engine light.

Thats it! Passed smog with flying colors and runs great.

Amazing how the MAF caused fuel system rich and fuel injector pulse width/high, not to mention a great loss of power and gas mileage.

Cause and effect here. Its just too bad the codes don’t give you the cause but just the effects. :angry:
As Ive learned codes are back door guides, but you have to get to the front door which is now back probing and testing the sensors suspected. :sick:

Hope this helps someone in the future when you get a code like or similar to these.

ON to the next car problem.
91 Nissan D21 truck with very bad idle. Runs great past idle.
I will post in new thread, problem and issue and fixes for this one soon.

Thanks for the help on this one thisisbuod! 😛

[Eric]

Coming to conclusions soon.
Will report back this week.
I think I found the fix and the issue. :woohoo:

[Eric]

OK….

So Im on the right track then. I will check IAC, TPS, MAF and EGR. Fuel pressure regulator as well. I was also told it sounds like a vacuum leak, so I will go hunting with carb cleaner as well. Unfortunately the Shop Manual doesn’t give me the specs on the IAC, TPS, MAF. Im assuming its universal on these, so I will go by that and see what I can come up with. Now I wish I had a scope to check the TPS sweep….What a pain!!! :angry:

Thanks for the great advice and I will post my results if and when I find it either way. I just wasn’t sure how to interpret the codes given. Its more like the codes given are what the sensor is causing other things to do but not pointing to which sensor it is…….frustrating. :pinch:

Let the fun begin. :unsure:

[Eric]

Hey Jotmon,
NO, actually I know the only adjustment is to set them up properly when installed. I totally get what you guys are saying and I know how one works. I just wanted to know the initial set up and if they were not set up properly, could I re check them as in re setting them up again just to make sure the plunger in them was centered properly and such.

Good point. Maybe they didnt replace them at all. Im just gonna replace them all and set them up properly. I just wanted to learn the proceedure on a 4 cylinder.

I think I confused everyone by all thinking I could adjust something on a hyraulic lifter.
I know once zero lashed and set properly, they do the rest. I was just thinking, someone might have not set them up properly and there for, they are not able to pump up and perform as they should.

Thanks for the help!

[Eric]

Hey Jotmon,
NO, actually I know the only adjustment is to set them up properly when installed. I totally get what you guys are saying and I know how one works. I just wanted to know the initial set up and if they were not set up properly, could I re check them as in re setting them up again just to make sure the plunger in them was centered properly and such.

Good point. Maybe they didnt replace them at all. Im just gonna replace them all and set them up properly. I just wanted to learn the proceedure on a 4 cylinder.

I think I confused everyone by all thinking I could adjust something on a hyraulic lifter.
I know once zero lashed and set properly, they do the rest. I was just thinking, someone might have not set them up properly and there for, they are not able to pump up and perform as they should.

Thanks for the help!

[Eric]

As college man asked…..what tuning did u do? Name it all. at high RPMs, it can be a lot of different things. IF it only happens are very High RPms, then it is spark or fuel related. Only driving it, could I tell.

But,,,…if u did tune up and now its happening, must be something u did in tune up.
You have to trace all of it down the to gap on your spark plugs. But either fuel is not keeping up or your coil is poooping out. Not to mention, if any of your sensors are not responding properly. To make it more confusing, all this can affect your timing.

Sorry for the confusion, but like I said earlier, it can be as simple as a bad connection to all of one of the things mentioned above. You might have to take it to a tech so he can diagnose it for you.

Sorry I couldnt be more help.
Good luck and let us know if you find the problem.

[Eric]

As college man asked…..what tuning did u do? Name it all. at high RPMs, it can be a lot of different things. IF it only happens are very High RPms, then it is spark or fuel related. Only driving it, could I tell.

But,,,…if u did tune up and now its happening, must be something u did in tune up.
You have to trace all of it down the to gap on your spark plugs. But either fuel is not keeping up or your coil is poooping out. Not to mention, if any of your sensors are not responding properly. To make it more confusing, all this can affect your timing.

Sorry for the confusion, but like I said earlier, it can be as simple as a bad connection to all of one of the things mentioned above. You might have to take it to a tech so he can diagnose it for you.

Sorry I couldnt be more help.
Good luck and let us know if you find the problem.

[Eric]

Hey WOODbar,
I got ya. So, your just saying, whether they were zero lashed and adjusted properly or not, they would compensate for the lash and they would stay quiet. Ok, so if they were over tighted or undertightend or just not set properly, they would still function quietly, correct?

So, at this point, I just want to know how to adjust them, so if I put new lifters in, I will know how to set them up properly.

Thanks for your advices
=)

[Eric]

Hey WOODbar,
I got ya. So, your just saying, whether they were zero lashed and adjusted properly or not, they would compensate for the lash and they would stay quiet. Ok, so if they were over tighted or undertightend or just not set properly, they would still function quietly, correct?

So, at this point, I just want to know how to adjust them, so if I put new lifters in, I will know how to set them up properly.

Thanks for your advices
=)

[Eric]

Yes, I understand they adjust automatically and theres no adjustment. But I want to re adjust them to zero lash and see if in fact they were set properly. My thinking is, if they were not zero lashed set properly, they are not able to make up the slack and the rockers are just clacking and chattering now.

Now, if thats not the case, then can I just replace the lifters without damamging the cam?

So, I just want to know how to set up the hydraulic lifters and so from there.
Thanks for your reponse and any more help.

[Eric]

Yes, I understand they adjust automatically and theres no adjustment. But I want to re adjust them to zero lash and see if in fact they were set properly. My thinking is, if they were not zero lashed set properly, they are not able to make up the slack and the rockers are just clacking and chattering now.

Now, if thats not the case, then can I just replace the lifters without damamging the cam?

So, I just want to know how to set up the hydraulic lifters and so from there.
Thanks for your reponse and any more help.

[Eric]

Year, make and model. Engine size and specs also. Carburated/fuel injected? Give the basics first, and Im sure some can help you. Its either electical or fuel related, but after a tune up, must be electrical. Check connections and sensor connections. Sounds like spark or timing.

[Eric]

Year, make and model. Engine size and specs also. Carburated/fuel injected? Give the basics first, and Im sure some can help you. Its either electical or fuel related, but after a tune up, must be electrical. Check connections and sensor connections. Sounds like spark or timing.

[Author]

Replies