New Problems, looking for possible causes

[mike95125]

Well My teener starts like a champ now. The next batch of problems is as such:
- It appears that #1 is back firing & #3 is, for lack of a better term, front firing through the intake and throttle body occasionally. Mainly a persistant crack in the idleing though.
- Have goofed with and continue to goof with the timing.
-I get a nice white smoke that eminates out of my exhaust when I rev the engine or when I go from open throttle to closed throttle.
My thoughts:
- I am going to recheck my valve adjustment tomarrow after I let it cool over night. I think that this may be part/all of the problem.
- Not sure if its benneficial or not, but I disconnected the MAP sensor while the engine was running and it "seemed" to get better. This perplexes me as the hose for the sensor was left intaking air yet the smoke disappeared, and the back firing decreased. Prolly unrelated.
- also it idles at arround 1200 rpm with the throttle bypass screw completely closed. I think my air bypass valve is Kaput!

What I need:
- Any of your advice on what to check and what to consider, what order to consider, yadda, yadda, yadda.

I intend to check my MAP sensor as per Brad Anders exceptional web page.
- checked and verrified FI plugs in right injectors
- checked inlet air temp sensor, its good
- checked compression: #1 122, #2 130, #3 115-18, #4 122
I had just re ringed these pistons and am using a fairley inexpensive compression tester. I hope all of this info can help you help me.

Many TIA
-Mike

[Jim Smolka]

A couple more things to check.

1. Make sure the cold start valve is not dumping in more fuel.
2. Check that the Fuel pressure regulator is installed correctly .
3. Check the Aux Air valve as mentioned earlier.
4. Make sure the dizzy is not worn out.

[mike95125]

Thanks again Jim! Will do. The rest of you guys keep em coming

- Checked fuel pressure regulator, I beileve it to be installed correctly as I can see no other logical way to install it.
- What exacxtly should I look for in the distributor?
- Can the fuel injection doo dad in the distributor be the cause for my two erratic cylinders?

[Dave at Pelican Parts]

Disconnecting the MPS hose should result in a large air leak into the manifold, and also a very very rich mixture. The MPS will see atmospheric pressure, which is interpreted as a wide-open throttle (and then a bit more!). This indicates a pretty basic problem with the mixture...

High idle in D-jet cars is caused by one of two things: Either overly-advanced timing, or air leaks. You can check to see if the Decel Valve or Aux Air Regulator is leaking by using a pair of vise-grips to squeeze shut the vacuum hose from one of those gizmos to the manifold. If the idle drops, that component is leaking. Remember, though, that the AAR's whole purpose in life is to be a vacuum leak--for the first 5-10 minutes of driving!

Bad trigger points would probably cause two diagonal cylinders to have the same problem. I don't think that's the cause... Check your grounds, though.

I suggest thoroughly checking your ignition system, then making sure the fuel and vacuum hoses are hooked up correctly and are in good shape (leaks are bad!). Check the fuel pressure somewhere between the fuel pump and the fuel pressure regulator (there are two ways to hook the regulator up!), and then dig into http://members.rennlist.com/pbanders to check the FI components.

--DD

[Bleyseng]

I agree with Jim's number 4-check the distributor for wear and the timing. A easy check is to check the timimg to see if it's at 27 degrees before TDC @3500rpm. When you look at the timing mark at 3500 rpm is it a blur ? spread over about a inch or so or is it a nice firm line not bouncing around. If it is a big blur, take out the dist. and check the mainshaft for play. There shouldn't be any!
Solution-get new or rebuilt and install a pertronix if you don't already have one. Good timing is very important on these motors.
Geoff

[mike95125]

Well, I just adjusted the valves and they were not in the best adjustment so it was a good start. How fun it was!
Now I started it up and I adjusted the timing:
- Still smokes like a chiminey (white smoke)
- still back fires a bit, real low and infrequent.
- now at 27 btdc the car idles at 2000- 2200rpm. A little clarity on
this point would be nice. It runs best when the timing is
advanced to what I think is ATDC.
-Is the notch TDC?
-Is the timing mark supposed to be to the left or the right of the notch as I am
looking at it from the back of the car?

I need to figure out how to get my guage to fit the fuel pressure nipple for that test. I am going to disconnect the CSV and see if that thins out my mixture.
- the timing mark stays pretty put, so I dont think its the
distributor.
- I am running a 1.7l dizzy on my 2.0, could this be the culprit. I
asked in a post a while ago if it was a prob and all signs pointed
to no.

When it is being driven it runns very strong, all I need to do is figure out what is causing it to idle high and what is up with the fuel mixture and timing. Ya, thats all

TIA
-Mike

[anthony]

>>- Checked fuel pressure regulator, I beileve it to be installed >>correctly as I can see no other logical way to install it.


I don't think the issue is installation but checking for the correct pressure. On my '74 2.0L the correct pressure is 29.5 psi.

[Dave at Pelican Parts]

For your timing questions, please see:

http://www.pelicanparts.com/techarticles/914_timing/914_timing.htm

27 deg BTDC at 3500 RPM with the vac hoses disconnected from the distributor.

ATDC is retarded timing, not advanced. Over-advanced timing will speed up the idle, while retarded timing will slow it down a bit. I'm guessing you're using the wrong mark, or setting it at the wrong RPM. Or you forgot to zero your timing light's advance knob if any. (Been there, done that!!)

--DD

[mike95125]

Ok disconnected my CSV and the smoking didnt change. It smokes mostly when I rev it...of course.
What I have done today so far:
- disconected CSV, no change
- arbitrarily adjusted fuel pressore, no change in smoking
- adjusted points, they were at high limit now at low, no change
- checked hoses for leakes, no luck yet.
- disconnected each FI wire one at a time to see if smoking
stopped, no change
- diconnected to find #3 is source of back fire (most likely), I think that the spak plug is not seated enough. why, I dont know.

I suspect that using the wrong dizzy may atribute to some of the problem, however I can not explain my rich running problem. I swapped out Brains, and MPS and no change in problem.

I am feeling close to my wits end. I dont know what do do from here.....AHHHHH!
Little better. All help apreciated.
-Mike

[BKOMAR]

Mike, the high idle may very well be your auxiliary air regulator stuck open. I had a similar problem (minus the smoke) and checked EVERYTHING for air leaks. I finally started tinkering with the AAR and that was the culprit. Do a search and you should come up with the thread. In a nutshell, I had to take it apart, clean it and readjust it to work properly. The car idles perfectly now and warms up fine. BTW: To all that had any interest in the "try different AAR's from different models of cars" experiment, the search and experiments are ongoing... I will have a report in the future, I expect in the fall (too many honey-do's). Good luck Mike, Brian

[mike95125]

Thanks for the encouragement Brian! I had checked the AAR and it is fortunately/unfortunately working OK and when I capped it off it had no effect. There must be something that I am missing. I am nervous about the rings that I put on the pistons. If the thick 4mm oil scavenger ring is not doing an adequate job, how would I know?

[Jim Smolka]

Did you clamp off the fuel line to the cold start valve. I have seen these leak...

[mike95125]

Yup, completely disconnected the fuel supply. No better.

[Bleyseng]

The only difference in a 1.7l and a 2.0l dizzy is in the advance curve and that is minor. I doubt that is your problem but white smoke doesn't sound too good.
Recheck the vaccum hoses to make sure they are to DD layout to cure the high idle.
Use starting fluid to find vaccum leaks that can cause high idle. When you spray alittle bit on a hose connection the idle/car speeds up.
Doesn't sound like you are timing the car right at all.
Geoff

[mike95125]

Tell me about it! If I go to the right of the deep mark on the fly wheel I get lower steady idle. If I go to the left of it I get steady high idle. It is almost as if the pictures on the tech article are reversed. I did exactly what the tech article said. I indexed the mark to the left of the divit for 27 degrees, marked it easy enough. I have checked my decelaration valve + hookups to and from it, MPS, all seals are new. My main concern is that of the smoke. I pretty much ruled out the rings that I installed due to the variability of the smoking with what control I have on the fuel mixture. Odd thing though, when I pull the hose for the MPS the mixture "seems" to get leaner not richer. The smoking becomes less! Wierd. I just took it for a drive and it is making good power. A red light on my combo gauge, top half started blinking though when I stopped to park. Is this an over heating indicator? Also, do all 914 shake on the freeway? The other one I had in 96 did the same thing. Thanks for reading and answering.
-Mike

[RustyWa]

Isn't the deep mark on the fan 27 deg BTDC? I've got a red dot at TDC and a deep line at 27 BTDC.

Reading your earlier posts, you say you made marks using the template and timed it 27 degrees left of the deep mark, but the car ran better when you advanced it....could it be because your actually advancing it closer to the real 27 deg BTDC mark? Hell, would the car even run 44 deg BTDC? Forgive me if I missed something.

But then again, I haven't gotten around to actually timing my car. I just looked at the marks.

[Bleyseng]

The lite of the upper half on the combo gauge is usually the parking brake lite.
Shaking on the freeway, no that is not common unless the last car you had a worn out front end/bad wheel bearings too!
I just drove mine from the middle of Oregon to Seattle without any shakes, very smooth at 90mph......
Geoff
(still think you have a vac hose wrong plus mistiming, pretty common)
PS. try plugging all the plenum vacuum nipples except for the MPS hose. Plug the AAR valve hose and set the timing like the tech article. Plug the vac retard hose back in. Then see if you can lower the idle speed with the air bypass screw on the throttle body

[mike95125]

Ok, I have a picture.
this is with the front of the car up screen. I have the notch and like I said the timing works better if this template is reversed in my car. I tried it exactly the opposite and it was pretty good, drove fine. I will block all of my hoses and try that aproach. It will be a while I got finals to study for. Prolly Friday night.
Thanks again.

[Dave at Pelican Parts]

A few things--
- arbitrarily adjusted fuel pressore, no change in smoking

Arbitrarily tweaking the fuel pressure is not a very good thing. You really ought to get a gauge hooked into the high-pressure fuel loop. I have mine on the hose that used to go to the cold-start valve. You want 29 PSI. A couple PSI higher will richen the mixture, a couple PSI lower will lean it. Too much higher, and the injectors will start to suffer (eventually leaking); too much lower, and atomization will get worse resulting in poor running.

Next, it looks like you're using the 1.8 timing template. This is not correct for a D-jet (1.7, 2.0) car. Take a look at the fan picture I posted down at the bottom of the timing article. It shows the TDC and D-jet timing marks in relation to the fan blades, in particular to the thick "block" where the fan bolts go. Check this against where you are setting the timing.

Finally, white smoke can be caused by a lean mixture sometimes. Pull the plugs and check the deposits. Black and sooty is rich, white or grey is lean, tan or brown is good.

--DD

[mike95125]

Yeah Dave! Now Im getting some where. The template shown has marks further to the left for a 1.7/2.0. I printed the template out from your web site and used it as perscribed, indexed it to the left of the notch. As for smoking, the pluggs were black and sooty but I had extra assembly oil in the cylender from just being assembled and that is probably the cause. I will check again.

What I am doing next:
- find correct index timing mark
- check pluggs again
- plug all nipples on the distribution mannifold vice MPS, and test for leaks.
- adjust fuel pressure to 29psi

I just read the comments above the picture. I set my timing to the wrong thing, thanks for the clarity. Consequently, I set my valves to 27 BTDC as well. A little knowledge can go so far. I cant wait to re adjust my valves again (smile through the pain). If I am correct then I need to index the template from the article so that the 27 degree mark ( obscured by the fan shroud in the picture) Is at the notch and go right from there. You rock! Thanks Dave.