Solid Snake

I bought the car 2 years ago when I was 21 and now that I have enough money to throw away, I decided to do some wrenching on the car. I tore the motor down to the heads/block. I took off the intake runners, the throttle body, the CIS system, de-gunked and polished everything. I replaced the spark plugs, vapor lines, intake manifold gaskets, the two rubber fuel hoses, a damaged CIS line, 95% of vacuum hoses and more.

I have been going ten weeks on and off with this thing and tonight I finally was able to crank it. When I did, nothing happened and so I gave the starter a rest and kept trying. Finally I heard some pops, then a few stumbles. Eventually, it idled like crap, maybe at 300rpm, it didnt even register on the tach. I temporarily retarded the timing completely which smoothed it out. Then I blipped the throttle - no reponse. I floored it and it kept stumbling along at 300-400 rpm. I gently tapped the CIS airflow plate and the engine came to life, it shot up to 800 rpm, but when I took my finger off it got crappy again. Obviously it is running lean, but I not sure why. Im fairly certain that all the hoses are in their places and I hear no vacuum leaks. Could degunking and reinstalling everything really throw off the tune that much?

As if that BS werent enough, the radiator decided to spring a leak and spray me with hot coolant in its gratitude for my efforts. DPO overtightened the hose clamp and cracked the fitting it seems.

On another note, I notice that the car blows smoke out of the timing belt covers and the oil fill. I see now why they routed these back into the intake. Is this normal?

I know this is nothing compared to the stuff some of you guys have gone through. I guess I wanted to vent more than anything. Do I need a special tool to richen up the mixture? That thing with the red mark on it on the CIS unit just seems to freewheel when I turn it. Are there any radiators from other cars that will fit ours somewhat well? Im not partial to the behr unit, especially if I can get a brand new one for half the price of a used original.

Lizard928

First off check the vacuum of the engine, to me it sounds like you may have a couple of problems and this is the best spot to start, check it with depressing the plate to get it to run better, and without.

Verify that the cams and crank are in proper positioning as well.

3000teeth

ummm.... this is way more than i've gone through --good f**king luck, that's all I can say.

-T

Mrmerlin

the smoke from the timing covers might be a problem , if it doesnt clear out when the engine warms up. What does the smoke smell like? If it smells like rubber then your water pump may be getting ready to seize, you can check the back side of the belt for traces of burning. If it smells like oil then this should burn off unless there is an oil leak. As far as the running is concerned, check the timing of the, distributor, cams and crank, check the plug wires for correct routing, install a new fuel filter , if you didnt , check the vacuum lines, try adding a bottle of techroline to gas, this may help the FI system clean out.It just might be something simple, take your time, you will make it right, Stan

By the way your not throwing your money away, your using it to provide yourself entertainment, and your investment in yourself will be worth it in the long run

Solid Snake

The smoke from the timing belt covers does clear once the engine warms up, however the smoke from the oil fill continues. I'm afraid to ask where this smoke comes from.

I haven't touched the cams or crank, I didn't strip it down that far.

I notice there's a special tool for adjusting the fuel mixture. Is it some kind of allen wrench? Is there a tool I might possibly have that I could adjust it with?

Lizard928

smoke from the oil fill is normal it is just airated oil that is misting out from the crankcase.

and the "special tool" you refer to is simply a 3mm allen key, but be forwarned, something isnt right and adjusting the mixture is not going to solve your issue I dont believe.

Solid Snake

Thanks for that info. Here's why I believe the mixture is too lean:

1. Can't be cam timing. It ran OK before the rebuild and I haven't touched it since.

2. Runs smoother when I fully retard the timing, suggests lean mixture.

3. Runs smoother when I touch the MAF plate, also suggests lean mixture.

4. Seems to be firing on all 8, stumbles noticeably when I pull any plug.

5. Plugs are brand new and gapped correctly.

6. It gets air, it gets spark, all signs point to fuel.

Things I can't rule out...

1. I did remove and reinstall the MAF plate, maybe this threw off the adjustment?

2. Perhaps one or several injectors are clogged. I will run seafoam and see if it helps.

3. Unmetered vacuum leak.

Any suggestions?

Lizard928

I believe that you probably have a vacuum leak, and i would never recommend removing that plate from the CIS dizzy.
first thing you should do is make sure that it is perfectly centered.
then test the vacuum as I had origonally suggested, check it with the idle running how it wants, and with applying alittle more gas via pushing on the meterplate. what are the readings you get.

Solid Snake

OK, I'll do the vac test as soon as I can ask my dad where the gauge is. It seems to have livened up a bit since yesterday and the day before. Now it idles somewhat rough at around 550 rpm, but it doesn't die. Throttle response is still really poor though.

I tried turning the fuel adjustment and it seems to do nothing at all. It seems to spin in place forever and doesn't go in or out. Is this normal?

Also, about the radiator, can the side tanks be replaced by a decent shop? I thought about taking the radiator around to shops to see if they could do it (they weren't sure) before ordering the part. Is it a safe bet that they can do it so I can order the tank today? Are the right and left tanks the same part?

Lizard928

right and left tanks are different. anyone who is competant should be able to replace the end tanks.

I havent done much on the CIS 928s, but if they are like the MB 450SEL then teh allen key goes into a piece that sits higher than the CIS dizzy housing which has a screw below it. you then have to push down on the allen key and turn abit to get it into the actual adjustment screw below. This can be tricky to do with the car running as the slightest push on that arm will increase the fuel.

Sean79 5spd

#1 is getting vacuum leaks taken care of, there are lots of areas to check including injector seals, intake tube gaskets and boots, throttle boddy boots and of course all the hoses. I presume you replaced all the hoses. The fact that you re&re'd the air flow plate (not MAF plate) is concerning, like was said ealier ensure you have it centered. Did you take the fuel distributer apart or off the air flow housing?
When using the allen key you must ensure that it actually seats in the mixture screw, use a flashlight to be sure.

Sean

Solid Snake

Thanks. I decided to get another used radiator from 928intl instead of messing around with a rebuild. Mine doesn't have an oil cooler, but the only ones they had were ones with oil coolers. Will I have any trouble fitting a rad w/oil cooler into a car that doesn't need it?

I've checked over the whole engine several times and can't find anything. I don't hear any telltale hissing except from the airflow plate. Maybe the EGR is stuck open? I did remove the CIS distributor from the housing, but applied a new gasket and the fit is very tight, same with the throttle body. The intake tubes are secured to the block very tightly and the boots are clamped down pretty hard. I made sure that the airflow plate was perfectly centered before I installed the unit back onto the housing, so it's not snagging anywhere. The car does run slightly better when I block off the tube that goes between the evap valve and the throttle housing as it causes more air to flow past the plate. I suspect the EGR port might be leaking, but I doubt such a leak would be big enough to make it run this poorly. I will look into it again when I get home at 5.

Sean79 5spd

If you have connected hoses incorrectly and EGR is operating at idle then the car will run very badly.

SharkSkin

I received an email recently from a guy having the same symptoms. His problem turned out to be confusion over the firing order. Make sure you have that right -- the cylinder numbering scheme is different from domestic V8s:

(F is front)

1 2 3 4
F
5 6 7 8

Dennis Wilson

Did you adjust your ignition timing? The initial setting should be good at TDC. Once it is running OK then a final set should be done according to the specs. Did you change or remove the idle setting screw when you had the intake off? I would also recommend checking for vacuum leaks, cam timing and ignition timing before adjusting the A/F mixture.

Dennis