OT '96 Saturn DOHC won't start

It's not a 2 cycle.

"PrecisionmachinisT" wrote in message news:jPGdnXN8R9fn_W_PnZ2dnUVZ snipped-for-privacy@scnresearch.com...

"a conventional four-stroke engine, this signal must also observe the phase of the camshaft relative to the crankshaft, so contact breakers are normally driven from the camshaft and distributor drive. With a wasted spark, the crankshaft can be used instead, as the system fires on both revolutions."

Like a 2-stroke.

jsw

(You're in my twit file, Doug. I see your posts only when someone quotes you. Ask Stryper for help, whydoncha? ;)

(You're already into it for more than a pro would have charged, and a pro would have a network of other -relevant- pros to fall back on for advice when they came up empty. I'm certainly not saying that the good folks here aren't knowledgeable, but I think clare is the only

-active- automotive font of knowledge here.

But it's likely documented by Saturn dealers and could turn out to be a $50 fix, or whatever their minimum is nowadays. I've been out of the field since '86.)

Absolutely!

I prefer the relative maintenance-free comfort of a newer vehicle, but you have a definite point there.

Sadly I know some "professionals" who are just as bad.

Troubleshooting is a lost art, and logical thought all but non-existant in the general population. Sure helps to understand the basic theory of how something works, too.

A badly flooded cyl can flood the rest of the engine too. Has the OP checked his oil level on the dipstick? If the injector(s) is (are) stuck open he will be "making oil".

My suspicion is he grounded his injectors by pinching a wire. I've seen it happen more than once. (never done it myself, but have had to fix a few))

Power is supplied to all 4 any time the key is on. The computer grounds the injector to fire it.. The 1996 SC2 is sequential injection.

If the belt jumped the compression will be below spec on crank.

ALL electronic ignition vehicles function that way.

It is also a "waste spark" engine - so the plugs fir TDC compression, AND half a cycle off.

But crank sensor only can't tell if the belt has jumped. Some engines (don't know about the Saturn) will not fire if the cam sensor and crank sensor are not timed identically (to prevent damage from running mis-timed)

Greetings Clare, The OP said that when starting fluid was used it backfired out the throttle body. In my experience as a shadetree mechanic when I experienced backfire it was either an intake valve or valves that didn't seal, for whatever reason, or the timing was off so that the spark occurred when the intake valve was open. What other conditions can cause backfiring on a fuel injected engine? It's nice to be able to ask someone who really knows about cars. Cheers, Eric

dpb wrote in news:lctj2g$1nf$ snipped-for-privacy@speranza.aioe.org:

Definitely not. I've checked that about five times now.

Saturn S-series engines use timing chains, not belts. I suppose if the tensioner broke, the chain might have jumped... but that seems unlikely.

Saw pretty much the same behavior on our other Saturn S-series last summer when the crankshaft position sensor failed. That tests good on this one, though.

snipped-for-privacy@snyder.on.ca wrote in news: snipped-for-privacy@4ax.com:

Oil level is OK.

So you think the injectors are running constantly, and flooding it? If that were the case, I should be able to smell it. But I don't.

snipped-for-privacy@whidbey.com wrote in news: snipped-for-privacy@4ax.com:

Faulty crankshaft position sensor that causes the PCM to think the crank is someplace it's not?

snipped-for-privacy@snyder.on.ca wrote in news: snipped-for-privacy@4ax.com:

The Saturn S-series engine doesn't have a cam sensor.

Larry Jaques wrote in news: snipped-for-privacy@4ax.com:

I think it's past time that I put you in my twit-filter too, since you obviously have no clue how to locate or fix the problem and hence have nothing to contribute beyond gratuitously obnoxious remarks.

Really? So far, the total is only about $175. The tow to a shop, alone, would be 40% of that.

So you clearly don't know what you're talking about.

Clearly you aren't, at any rate.

*WHAT* Saturn dealers?

No, you're not out of the field at all. You're still way out in left field.

Especially if you think you can get anybody to look at an engine for fifty bucks.

Idiot.

I've had badly flooded engines backfire on ether. That engine needs to be "dried out" which may require changing the oil, and it needs clean dry plugs. It also needs to be checked for injector pulses - a set of "noid" lights would make the job easier. If the injectors are not firing it COULD be a bad sensor - but if they are on steady he has a bad engine control computer or grounded harness. Disconnect the computer, if they still stay on the harness is at fault. If not, the computer.

I think you'll find that Larry is out in -Right- field. Eric

On 2/5/2014 1:39 PM, Doug Miller wrote: ...

I've seen 'em get off a tooth (or break a tooth or the like) but as somebody else noted, that you seem to have good compression means mechanically it's in synch within enough it ought to fire lacking something else. May be time for new for PM, but it ain't the present problem.

Then the firing order is suspect or you put the cam back in 180 out or something similar to have the intake valves open when it fired. As again somebody else noted, there's no back fire thru the throat if intakes are closed when it fired so they weren't.