Won't start, Backfiring from intake?

[Taek]

Hey all..
I just put a new timing chain / Cam Sprockets and a crank sprocket on my 92' Grand Am .. Its got the 2.3L DOHC Quad 4 in it.. Its timed exactly as it should be, As far as how I've been told to time it, From a couple people I know and using the Chiltons Manual .. I've cranked the Cams over until the the alignment dowels fit into the cam sprocket fully.. On both .. I've lined the crank sprocket up with the dot on the sprocket itself and the dot on the side of the block, Fit the chain on tightly, Its not loose anywhere.. I've turned it over twice by hand making sure nothing was hitting.. Now when I try to start it, It just continually turns over, And occasionaly backfires from the intake I guess ? .. To me it acts like its out of time.. But I dont see how it could be..
Any help on the situation would be greatly appreciated =) .. Thanks!

Please try not to be jealous of my freaking awesome paint skills..



Tell me if I've done something wrong as far as how the timing should look..

[gmack221]

sounds like your on the right track with it being timing, take the cover back off and crank the motor over a couple of times by hand stopping at top dead center (when the crank is at its marks), make sure the cam dowels still line up. Sometimes a little slack in the chain makes it almost jump a tooth while installing the chain, its not cut and dry, you have to double check it... I didn't take the time to double check mine & ran it for 10,000 miles with the exhaust cam off one tooth after my rebuild ... oops it only ran bad at idle!

I would guess this is your problem, if it isn't next thing I'd check is to see if your getting spark on all 4 cylinders, if your not reply back with where you have spark & we'll do our best to help you pin point the problem.

[Taek]

Ok.. This may be a stupid question to some of you.. But I've never worked on a distributorless engine.. No plug wires and what not.. Whats the best accurate way to check for spark ? = / ..

As for the timing.. It checks out perfectly everytime I rotate it.

[gmack221]

thats not a stupid question at all ...
1. disconnect electrical plug on the top cover (says quad 4 on it), then remove 4 bolts and flip over, re-install one of the bolts to hold it upside down
2. remove the 4 small plug wires
3. install 4 regular plug wires, 3 from coil housing to plugs, 4th from coil housing to spark tester ($10 at autozone).
4. connect electrical plug back to top cover
5. move spark tester thru all plug wires

if you have
1 cylinder no spark its most likely a coil housing thats bad
2 cylinders no spark its most likely a coil (1&3 or 2&4)
3 cylinders no spark both coil & coil housing
4 cylinders no spark start with a crank position sensor, or ignition control module (where the electrial connector connets to top cover).

Why did you put a timing chain on this to start with, describe the orig problem (why you started working on it), and what you have done, maybe that will help us help you ... The whole story will help us help you diagnois the problem

If you have spark, and your sure you timing is correct, turn your key to the run position (without engaging the starter) & make sure you get a check engine light (this tells you if you computer is powered up or not), I had a wiring problem not letting the computer get power, wasted lots of money on parts before I replaced the wire (it was broken somewhere).

[Taek]

Very good point.. I got the car off a friend who said he took it to a shop after it dying rather abruptly on him, They told him that the timing chain snapped, most likely due to the water pump freezing up.. So I got it off him cheap as he wanted to avoid the hassle of changing it himself.. Well.. I tear it all down.. The timing chain looks great, But the 2 cam sprockets were worn down and missing teeth, And the water pump was fine.. So I replaced the timing chain, cam sprockets and crank sprocket.. Which is where I am now.. With a car that isn't starting and backfiring from the intake =P .. The car sat for about 2 years before I got it.

[gmack221]

buy or borrow a compression tester, start there, if the timing chain skipped a tooth then most likely you have a good chance of having a bent valve (I think these are interference motors, since it has a timing chain & not a belt), which might explain the backfire. I definitly recomend putting a water pump on it, it is a pain and is the major cause for overheating & blown head gaskets on these cars, call it preventive maintence! I believe your compression should be about 120 lbs give or take, im sure you can find the spec in haynes manual on the autozone rack. If you have good compression continue with what I told you, but start there. Incase you don't have compression tear it down to see whats wrong, just an For Your Information, if you tear it down take a close look at the #2 & #3 piston, they are known for having rod bearings go out, if its not black on top its been touching the head & your looking at a rebuild or yard motor. Here's a good link about these motors, it gives casting numbers for the different generations, and all kinds of good info about the quad 4 parts. http://www.babcox.com/editorial/ar/ar40032.htm

good luck and I hope its something simple, post your results to help others find their problems, and of course any more questions you have.

[Taek]

Thank You very much =) , I really appreciate all the info.. I'm gonna go see if I can rent a compression tester.. I've been getting mixed answers about the interference thing.. Most people have told me that its " not " .. But that they're not 100% positive, and a few people have told me that it is, And again, not 100% positive heh..
Anyway.. I'll post back soon with my findings ! .. Thanks again !

[bjobotts]

Can definitely tell you that on my 2.3l SOHC '93 grand am that everytime it backfired out the intake it bent a valve. If it cranks really fast now then you have no compression. If not cranking really fast then stop cranking 'cause on mine with each backfire I bent another valve. 3times...3 bent valves...then got guage from autozone(they rent them free) and had one cylinder with good compression left. Timing not right or tensioner not working. Good luck

[Taek]

Yeah.. Its sounding like its going to need a rebuild .. I have a friend dropping me a compression tester off later today.. *sigh* =(

[gmack221]

don't give up yet, might be able to get away with a junk yard head, or having the one on there re-worked. If you get a junk yard head make sure you take it somewhere & have it checked for flatness, slop in the valve guides, & put new valve seals on it. but do all that before you got thru the work of putting it on, and remember if you replace the head you also have to replace the head bolts, the are torqued so tight you streach the bolt, so they are only good once.

[Taek]

Right.. I went in today to the local " head rebuilder " .. He basically told me if that whole head was shot, The highest amount of cash it'd take to rebuild it would be about $480 .. Thats with the head set and bolts and everything.. All new valves blah blah.. I looked on Ebay today and I can get a rebuild head along with the head set and bolts for $3-350.. Give or take.. Dunno what'd cost to get a junk yard head and make it " good " .. Still waiting on that compression tester to see how bad it is..