Hi,
My girlfriend has a 2000 blazer, and starting last spring it was starting to run a little rough. Then it would turn over but really hesitated to start and sometimes backfire.

Now it's running really bad, and losing power.

The first shop we took it to, said it was a bad fuel pump. We had it replaced didn't fix anything. We took it back, and they replaced the pump again. No better, we took it back this time they said it was a bad relay. Replaced that, didn't help at all.

Next we took it to the chevy dealership, after 3 days they said 'we can't find anything wrong with it' when we went to pick it up, it almost didn't start.

Finally we took it to another shop, he had it for about a month and couldn't figure out what was wrong.

So now after 3 shops and a few hundred dollars in troubleshooting, the car is still not running right.

The last shop said maybe it could be the 'spider injector'. But he wasn't positive and said it's just a guess. Said we could buy a used one and see if it would help. but I'm not sure if that's what we should do.

We tried to run codes on it, and it comes back with a MAF code I believe. But everyone says that wouldn't cause the symptoms we are seeing.

Does anyone have any ideas what we could check next?

This is a car that she really just wants to get rid of at this point, but we won't get anything the way it runs now.

Thanks!

 

Oh and something else I just remembered too.
It all of a sudden lost heat too, just blows cold air. I checked the coolant and it's full, and the car runs at the right temp.

 

You can clean the MAF sensor with CRC MAF cleaner. Have you changed or checked the distributor cap and rotor? If the cap is pitted or corrodid up it will run like crap with bad miss and possible misfires. I would check that out and your spark plug wires.

 

Tonight I changed out the cap and rotor, and it still hard starting and idles rough.
One thing I notice now, I hear a random clicking type sound and it sounds like its coming from the Cap and Rotor area. Could that be the wires? I could replace those next if you think that noise could be coming from those?

I also cleaned the MAF as you suggested with that cleaner too.

Oh, for the no heat.
Do you think it's most likely the thermostat?

Thanks again for your help!
Chris

 

Going to assume that the simple things have been checked: spark plug wires in good condition and all tight to each plug, same for coil wire, wires at distributor cap.

Check the color of the arc at the end of the spark plug wire. Needs to be a nice blue color.

The clicking sound is most likely the rotor hitting the inside of the distributor cap due to worn bushings. This should not prevent engine starting unless really bad. Just make sure the rotor screws are tight. Plan on replacing the distributor with an aluminum shaft one, about $50 from Skip White on ebay.
Borrow, rent an fuel pressure gauge and do a search here for doing a fuel pressure test.
It could be the spider needs replacing as it is leaking. The fuel pressure test will tell is there is a leak in the system.

Could also be a clogged catalytic converter due to an over rich fuel mixture. Try removing the post cat O2 sensor to see if idle improves. Will set the Service Engine Soon lite, so this will need to be cleared afterwards.

The no heat is probably a clogged heater core. If the coolant temp shows normal temp, then check the temp of the two hoses at the firewall. Both should be warm, if only one, then time to flush the heater core. Do this gently. If coolant temp is low, then yes the thermostat is stuck open. (The one in my '02 is stuck open....again!)

Let us know what you find.

 

...I agree.

 

Thanks for the tips, going to try and do some of these next weekend.

How much is a fuel pressure gauge? I thought my dad had one, but he didn't.

One thing I saw it do the other day, the SES light was blinking when driving, but then solid at idle. Does appear to be doing that now though.

From what I've read, that means a misfire? Is that right?

 

Clogged heater core is my bet. But since you're at it check your thermostat.

Heater core = Problem when cold air but engine correct temp.

Thermostat = Problem when cold air but incorrect engine temp.


The rest may be a bad fuel pump. In my old 98 blazer I had huge issues between it dying, hard to start, and other issues with that cause of the fuel pump. I went to Autozone and bought one under a warranty and went through 4 of them before I was told the autozone ones won't work by my trusty local mechanic. He sent me to Ebay and told me what to search and it has to be a rebuilt fuel pump. I got it and it worked great till I blew the transmission one night... That lead into another nightmare that ended in that blazer sitting in my yard lol.

But that could be the issue but I'm not sure. I wouldn't say this would be your silver bullet, but that worked for me. Get a fuel pump regulator to check your line pressure and see if it really is the fuel pump. If so buy a rebuilt one and I'm certain it'll solve your issue.

If I remember correctly the line pressure should be at 62 or between 60 and 66. Any less and the fuel pump is failing.

 

I'm going to try and mess with it again this weekend, I need to get a pressure gauge, will this work?
Fuel Pressure Tester & Fuel Injection Pump Tester

next, where do I actually connect the tester to get the correct readings?

 

Yea that should have some fitting that works.


After all of those guys looked at it my guess is a bad cat and for the heat shot blend door actuator.


It sure could be anything else the guys tossed.


Need a new distributor could be a real good guess also.


To the right of the distributor, drivers side you will see two lines one will have a threaded nipple. That is were you attach the fuel pressure gage.


From the front of the car to the right of the distributor you will see two lines, one will have a threaded nipple. That's were you screw your fuel gage on.


My problem is the guy who put two new fuel pumps in never did a leak down, WTF!