I just bought this 91 firebird not running for a couple hounded bux the guy said it had intermittent spark. Get it home and right off the bat I notice the plug wires were in the wrong order, so I ended up getting a new distributor modual cap rotor wires and plugs. I tryed that and it wouldn't start good spark though. Turns out the fuel pump also crap just replaced that and tested it I've got good fuel pressure at the fuel rail, but still won't start. No engine codes either. I'm at a loss, when I crank it it turns over great but seems to act like its missing something. Any ideas ?

 

Coil?

 

perhaps the timing is off?

 

I havnt checked the timing yet, if I have spark wouldn't that mean my could is still good though

 

If you got spark and fuel, I agree with fervernt that it may be timing. Need to rule that out.

 

I don't have a timing light could some one give me a run down on how to re set it. I assume piston one at the top of the head and as for my distributor what's my plan

 

Thank ......

 

I've owned a 91 Firebird for several years now and a few years ago I was having intermittent starting problems that even a reputable shop couldn't figure out which is when I discovered that the stock GM Multec fuel injectors are notorious for shorting out. You can find all sorts of information online about the fuel injectors being a common, significant problem on the V6. It's pretty simple, if only a little time consuming, to change the fuel injectors out and I wouldn't be surprised if that's your problem since you've tackled the other main culprits with no luck.

Linder Technicals Services is where I bought my replacements and have not had an issue since changing them a few years ago. Linder reconditions and flow matches injectors so you actually end up with better than stock injectors. They also have been doing this for years and have identified commons models with injectors issues so they have found replacements for the stock injectors with those common problems. For the 1991 Firebird you can get Bosch DRI direct replacements from them which is what I did. Their website is http://www.lindertech.com/reconinj.htm

 

Check for a code 46... If that's present, you can crank it over all day and it won't fire due to the injectors being turned off. Thanks to the VATS or some issue between the VATS module and the ECM.

And, again, check your timing. Keep in mind #1 cylinder is PASS front and not driver's...

Also check your ACTUAL fuel pressure. Just because it has the capability to spray out of the test port doesn't mean it has the required 37 PSI to run the engine. Changing the fuel filter might be a good idea since the dead pump and bad fuel probably plugged it good.

 

Ok last night i got it started re set the timing its ran great then this morning i tried to start it and nothing. It acted like it had never started so i took it apart re set it again and nothing so im realy lost. I have a video of it running from last night ill try to post it

 

So maybe im doing something wrong. I set my ballancer timming marks to 0 alligned with the notch (whitch notch?) And when i use either or the number one cylinder wont be at tdc by the way. So ive tryed going by the cylinder being corect and the balancer wrong and visa versa. Instal my distributor with the rotor on cylinder one plug wire. So where and what is wrong with this picture because im not sure

 

Well thanks for all the help guys ? This site seems to be less and less help full as i actually try to ask questions.

 

no clue, old 305 Camaro, when I kept losing time, was a bad timing chain.

starting fluid is good for testing, if it wont even try and start, you have bad spark [ even out of time, should atleast pop if spark is good] if it odes try to start then dies, you have a fuel problem.

 

Don't get so frustrated man, we do try to help out, but we can't all be on to just answer your questions as soon as you ask them. Its also rather difficult to do this without the right tools. Timing light is a MUST to try and time it. No way around that really. Have you checked your fuel filter? If its clogged that will lead to a no start as well.

 

You will get it figured out if you dont give up, but there are so many reasons why a car wouldnt start that you have to just keep tearing at it until you find it. I mean, it could be any number of things. Have you looked at buying a shop manual? There are some good diagnostic charts to help with this kind of stuff. Do you have any history on the car? Records, maintenance logs, anything? Right now in simplest terms, you are missing at least one of 3 things. Air, fuel, or spark. Easy to test for a fuel problem with starter fluid, as posted above. With spark, there are ways to set the INITIAL timing on here and many other places. You still need to set the timing with a light to get it to run right. Air is fairly self explanatory, check your filter, if its clogged to **** replace it.

 

The mark on the balancer is only for timing once the car is running. The computer in these cars will advance and retard the timing, so that mark means nothing until you have a light and the car is running.

 

I thought i had cleared this up
Great spark
Perfect fuel and pressure
Air is great

So im trying to get my timming at a starting point wheres my starting point. ?????

 

the stock balancer sometimes fail and things get off, as the inner and outter parts of it have rubber in the middle like a motor mount.

yank valve cover and get 1 spark plug to right TDC by eye[ 4 stroke], should start

 

Do i have to pull tve valve cover or does pulling the plug work just as well ?

 

Pulling the plug would get you close but you have to make sure you are at the top of the compression stroke, not the not the exhaust stroke. Pulling the cover only ensures this. You can pull the plug and put your finger over the hole to feel pressure.

I didn't see whether or not you checked the ignition control module. They will sometimes work but when they get warm the die again. When mine went out long ago it would let me drive about 2 miles before shutting down. Luckily I was able to limp it to the parts place (by then I had figured out the problem). One thing I had to do with my cousin's 92 V6 was the distributor itself took a dump and we replaced the guts. It would run some days and then all of a sudden lose time.

 

The mark on the balancer will line up with the timing tab on TDC #1, and TDC #4 IIRC. Thats why it would be best to pull the valve cover to make sure the intake valve has just closed as you rotate the engine to #1 compression stroke. That will be your TDC on #1.

When I first got my 89 RS, we would set the timing, and a couple days later it would run like crap. Come to find out that the timing chain was jumping teeth. Replaced that and all was well.

OP, I dont remember if you replaced that or not, but if not and you still cant get it started, it might be worthwhile to take a look.