I have no spark on my 2.8L S10 Blazer - I cannot figure out why. This is the story of what has been happening to me the last week or so.

I would be driving the car and all of a sudden "kaplunk" {the engine dies} either when I am driving or at a stop light... Just randomly. Not often. Then as two days go by it starts doing it much more often so I poke my nose around the fuel filter - which at this time definately needed to be changed! It was a F21111 and the filter new comes yellow, mine was brown and the plastic was heavily stained... So i figured, Ahhh... must be the filter!

As I am leaving work to go home to change the fuel filter I bought during lunch... The car dies @ an intersection (30 seconds worth of running..) and I am forced to push it across to the local 7-11. After an hour (and changing the filter in the parking lot) the car starts up only to go 200 feet down the road to die again, this time for good. Since then I have not been able to start the car.

Upon inspection I am not receiving a spark. I have changed the module, and the coil and still no spark. The car ran fine (idled very well even) when it did run prior to this incident.

I have poked around the forum and havent' been able to find much on the 2.8L, more so the 4.3L . . . . . . . I'm clueless here and I'm so confused on what I should do.

How do you troubleshoot a distributor, or what have you? At what point do I look to see if it is the ECM? The module is getting power according to the little volt meter i have used on it only up to like 5v though??

Any and all help could be greatly appreciated, I have just ran into so many awkward problems since I have bought this truck - I wish that I had not at this point.

It's the 4x4 Tahoe packaged S10 blazer if that matters...

I know it isn't getting spark because:

1) the fuel pump turns on
2) w/ starter fluid the car will not turn over
3) stuck a screwdriver into the ign.coil wire and ... Nope! no spark! {spark would give you a click noise} (bought a new one, same trick, neg!)

---- Added info: I own the haynes manual, but it doesn't tell you phooey about this kind of stuff- PLUS, the "wiring diagrams" given - suck. I have a 2BL carb and the book only shows you the fuel injected models wirings. So things have been a bit complicated... not to mention the distributor is on the back of the engine (bad chevy engineers, bad!)

 

another question to add...


When do you know when ignotion pickups go bad?

Mine seems relatively old by looking at its connector to the ign. module and the appearance of the wiring for that plug.

 

you can try checking the wire going to the coil. see if the coil is getting power. that wire may have broke

 

Okay, well, so far I have:

changed ignition coil
pickup coil
ign. module


still no spark.

I just found out there is an ECM on this car, but I do not know where it is located? I see now there are two fuses for this (ECM), and i haven't been able to find the fuse box either. Until saturday I am not able to work on this POS.

Also, I have located a part of ignition wire that appears to have a very "neatly" placed slice, which I blame on a ... crooked mechanic, which is why I do not like going to mechanics; (recently had work done a month ago... since then problems after problems I think they (mechanics) are all crooked.) This slice HAS to have been caused by a razor, it is too fine to be anything else and it exposes the wire- it looks like also there is some oil/grease that may have contaminated that part of the exposed wire- I tested the line and it is recieving 12v + at the plug to the ignition coil... So I don't know if to rule this out as the cause?

I'm at my wits end here as to ... What direction to go with this. Other mechanically inclined individuals, I request your assistance in helping me get my stuff back on the road...

 

...This forum is not working today!!

Anyway, I have:

changed:
-ignition coil
-ignition module
-pickup coil (wire/plug broke off ... oh well!)

I am still not recieving spark. The Ignition wire to the Coil is getting 12v+ - Also I noticed there is a "finely made" cut into that wire farther down towards the firewall, it doesn't "cut" the wire, but the rubber around it, there is some exposed copper... It appears there is a little bit of grease/oil on the wire there as well.

Would that cause an interference of some kind? Like I said, the plug to the coil is getting 12v+ ...

I'm at my wits end here.

I have guessed it's time to follow the wire to the ignition itself to see if it is corroded... Or to check grounds, but I don't know where the grounds are for this - so I've got myself a copy of the wiring diagram from chiltonlibrary

Can someone help provide some other points to look at and go over? I love this truck because its very "simple" but ... what's the deal!! ...

I just found out also there is an ECM. How do I check to see if that is bad? I get fuel, so I wouldn't figure the ECM would be bad? Also I understand there are TWO fuses for that thing?

 

The should be located under the dash near the glove box.

I am not sure if the 2.8L has the same ESC (electronic spark control) module that the v8's have or if that is what you are calling the ignition module, but that would be a place to look. Besides that, it sounds like you have replaced just about everything else already. Aside from components, the wiring would be the next thing to pour over.

 

A cut in the cover of the wire won't harm anything as long as none of the strands are broken or the exposed wire looks like it's covered in "green rust" if so, it's corroded and very brittle and likely on it's way out. If it looks fine, just cover it with some black tape. How exactly did you check for spark? Was it at the coil or at the plugs? As already mentioned, check the plugs that connect the wires to the coil, ignition modules,etc. some times when people remove them they don't fully expand the little clips that hold them in place and then pull on the wires to remove them. What will happen then is the wire will break or pull out of the socket and the plastic coating on the wire will stretch so there will be no visual indication that it's come apart. Had that exact problem myself and was hard to finally find.

 

well I have got spark now; it seems the module was wired incorrectly (i wired it in the dark last time) - now finding the timing is a bit harsh, so I must venture to get a timing light...