1997 Blazer Won't start

I have a 1997 Blazer 4 dr 4.3 Vortec. The engine all of a sudden will not start. I can hear the fuel pump run when I turn on the key. I put some gas in the throttle body and it fired right up till it ran out. I'm thinking maybe the fuel filter or fuel pump? Can someone please help.

I would definitly change the filter out..you need to get a pressure test of the fuel system...I believe you can rent the tester from autozone and it connects to the schrader valve on top of the engine on your fuel line (looks like a tire valve, may have a plastic cap on it) keep us posted

I'm hoping it's the filter. Someone said maybe an Ignition switch? Can't understand it being that though because the fuel pump runs.

If you search these post on 97's they seem to have a problem with there ignitions...not where the key goes in but the black box containing all electrical connections and such...

I hate to buy the ignition though if I don't need it. It's 90 bucks.

Check you fuel pressure first with the truck off and the key to the on position.

That way we can rule out a pressure problem.

Thanks for the advice. I'm going to rent a pressure tester today and check it. Going to pick up a fuel filter too for the heck of it.

Yea, that would be a good start.

Fuel pressure reads 45 with the old fuel filter. Still reads 45 with the new filter installed. Still will not start.

the pressure should be around 58 to 64 psi with key on, not running and drop 3 to 10 psi when running...good luck

So I guess I'm replacing the fuel pump?

the pressure should be around 58 to 64 psi with key on, not running and drop 3 to 10 psi when running...good luck

Notstepping on your toes, but for the 1996+ CSFI, it requires 60-66psi.

He is WAY below what is needed.

kc8ieg,

Check the battery voltage. The battery could be weak which will cause the low pressure from the electrical fuel pump.

The battery is new. It might be a little low due to all the crankin lately though. Was hoping it wasn't the fuel pump but it's not looking good.

Disconnect the battery from the cables and charge it to full before you do ANY fuel pump work.

the pressure should be around 58 to 64 psi with key on, not running and drop 3 to 10 psi when running...good luck


I'm a 97 Blazer owner and here is what happened to me today... My engine was at times hard to start and I think I noticed more throughout the day vs my first start in the morning. When this happens it takes about 4-5 cranks vs 2-3 to start the motor and then it may spudder a tad before the other cylinders kick in.

You get the idea. This is not a real problem, but with all the talk about ingnition switches (harness) going bad on a '97 I thought I would first rule out the possibility of my fuel pump system while I still had it running and could drive it to the mechanic. Here's what we found with regards to fuel pressue:

Key on ==> Pump holding steady pressure at 63 PSI

Start engine ==> Pump held 63 PSI for 2 seconds and then droped to 55 PSI

Engine off ==> Pressure dropped to 49 PSI

My mechanic checked his computer (reference manual ?) and said:

-- 63 PSI was normal as was the drop in fuel pressure after the engine started.
-- He ruled out priming to be a problem.
-- He said if the pressure regulator was leaking fuel into the manifold I probably would be seeing black smoke out the exhaust (and there isn't any).
-- He concluded that one or more of the fuel injectors maybe clogged and therefore may not be closing all the way... which results in fuel leaking into the cylinders. This means that too much fuel may be in the cylinder and could make it hard to start. (I also don't like the sound of fuel washing down the cylinder walls!)

His solution was more of a preventitive maintenance approch. He said I should clean the fuel sysyem by using the type that disconects the fuel return line and cleans the fuel ??? something-something, but not the type that you squirt down the throttle body.

Now here's the kicker... On my way home, two blocks from my house, I accelerated from a stop sign and the engine just quit. Still rolling I put it in neutral and tried to start it... Nothing for the first 8 cranks. Tried again and I got the car started, accelerated, and the engine quit. Put it in neutral, started it up and pulled in my diveway backwards just in case I need a tow in the morning.

SO..... What do you all think this could be? Fuel pump, fuel regulator, or ignition switch???

I was told that the fuel pump either works or it doesn't. If this is true then I'm leaning to replacing my ignition switch. However, I am surprised the shop manual says it will take 2 hours to replace. BTW, Advanced Auto Parts sells an ignition switch for $75, but I noticed that list is $165. That leaves a lot of margin on the table. Best to shop before you buy.

switch

Misfire in the cylinders from the injectors would throw a code.

I will fully charge the battery tomorrow. I need to get this thing running. Don't think the battery is too low though but I'll try anything.

switch

Misfire in the cylinders from the injectors would throw a code.

What if it's not a misfire... Electrically speaking? And yes I sometimes do get a "check engine light" warning, but when I check for codes there isn't one. My guess is that the computer resets with every turn of the key, but sometimes does not clear the "check engine light." I believe this is called a soft code.

So where does that leave us? I think I have an intermittent electrical problem which results in a miss. This electrical problem could be a bad ground (but where), or it could be the fuel pump relay, or it could be a clogged fuel injector, or it could be the fuel pump regulator??? Or how about the ignition module???

I don't want to get stranded, and today was the first time the engine actually quit after I accelerated. (This happenned twice!) ...But why would accelerating cause the engine to quit unless it had to do with the fuel pump electrical system momentarily cutting or loosing fuel pressure, or perhaps the spark was disabled to all the cylinders?

Simple question: Could all of the above be linked the ignition switch (harness in the steering wheel)?

Now I'm really reaching the edges of "what I don't know" so if anyone wants to place some bets on what my problem might be I would appreciate the help.

Yes.

With what I have described, do you think it's the fuel pump, pressure regulator, or the ignition switch?

Did you charge the battery?

It could be any of the three really.

Anything else happening? Weird gauge movement etc?

Battery charged. No difference. Local garage says fuel pump. 300.00 plus 75.00 labor to put it in. Heck I don't know. I just need my wheels back.

You have your answer of what the problem is LOW FUEL PRESSURE. 45 psi is WAY WAY to low

You have your answer of what the problem is LOW FUEL PRESSURE. 45 psi is WAY WAY to low

True, but is the low pressure caused by the Regulator or the pump?

Pinch off the return line and see what the pressure does

For the question of the ignition switch problem on the 97 blazers. I had experienced this curse first hand (Twice) and not being a mechanic but having a background in electronics I dissected the switch and found the problem. I hope this will be helpful in determining your problem. The first time this happened to me it interupted the power to the engine. the second time it messed with the Tranny. I would suggest saving a little $$$$ and doing it yourself but either way if your having the problems you need to replace it soon.

The problem is buildup on the electrical contacts. there are six contacts that go to different parts of the vehicle. The buildup, in the early stages, will allow current to flow through sometimes, allowing you to drive like nothings wrong but a sudden bump in the road could leave you sitting. Eventually it will get so bad that it will not allow the current to flow at all (hopefully your home when this happens).

As I said this happened to me twice. the first time i cleaned the contacts instead of replacing it. thus led to the second time which i replace it. Good luck

I'm hoping it's the filter. Someone said maybe an Ignition switch? Can't understand it being that though because the fuel pump runs.


See new thread on How To Change Your Ignition Switch if you decide to do this yourself. I'm not saying that this will fix your fuel pump pressure and other problems, but if you do decide to replace the switch... per the experts recommendations... not mine... I would be interested to know if a new ignition switch fixes your problem, because then I will know I did the right thing changing my switch before I got stranded somewhere! Good luck.

It was the Fuel pump as suspected. Thanks everyone for the advice. Runs great again.

Good to see you back on the road.

I have to take it back monday. The tank is leaking on the top. Found it out when I filled it up. I can't win.

That will be the shop's fault.

No worries, they will be able to fix it.

All fixed and rollin again. They had the o-ring on the fuel pump pinched and it was leaking from there.
I filled it up and no leaks so far. Blazer lt, where did you get your headlight covers and exhaust?

All fixed and rollin again. They had the o-ring on the fuel pump pinched and it was leaking from there.
I filled it up and no leaks so far. Blazer lt, where did you get your headlight covers and exhaust?

Headlight covers can be cheaply purchased off of ebay or your local parts stores.

Ravin Muffler and new Magnaflow carsound highflow cat can be installed at Midas.

I love them both, trucks looks and sounds good.