Grizz87

So I put new injectors in. It starts now but will not run. Back fires and dies. I'm wondering if I put the injectors wiring on wrong for the ones right next to each other on both sides.

kestell123

More details about what you are working on would help . If I remember corectly the TPI were batch fire so it would not matter. Sounds to me like retarded timing.

Tuned Performance

iTrader: (92)

2.8 is batch, how can it start but not run ? Runs and dies ? Was this running before the injector swap ?

Grizz87

its a 89 firebird 2.8l

Grizz87

was not running before the injector swap. replaced the injectors and the fuel pump. it tries to start but back fires and dies. not sure what else to check.

Tuned Performance

iTrader: (92)

no one can help you with such vague details

Tuned Performance

iTrader: (92)

constant hot spark ? Tuneup items in good condition?
compression is good ?

Grizz87

what other details are you needing? car is an 89 firebird 2.8l (listed on my profile as well). car turns over and starts and dies immediately after backfiring. only runs for like 3 seconds. Really not to sure what other way to describe that.

Grizz87

it is getting spark. has a brand new fuel pump, installed today. plugs, wires, and cap was done a few years ago before parking.

Tuned Performance

iTrader: (92)

What all have been checked, so assuming it ran when parked.
timing shouldn’t I’ve moved but will it run off starting fluid ?
fuel pressure verified despite a new pump . Not sure if it’s possible to use a noid on a 2.8 which plenum on but 89 had vats on the 302 ecm. It’s obviously getting some fuel or could be over fueling. Try clear flood mode ? Plugs condition are dry ?

Grizz87

I don't have a gauge to use to see the actual PSI but there is fuel in it as I can get spray coming from the valve. Vats has been bypassed years ago and has ran ever since it was bypassed. It did run before parking. I am not sure what you mean by flood mode and I haven't taken the plugs out yet to look at them. the timing was set with the old bad injectors in through.

Spark has been verified, fuel is at the rail, fuses are good, relays are good

kestell123

Clear flood mode is holding the throttle all the way to the floor while cranking. This should shut off the injectors , so if you were over fueling or flooding it would help clear the flooding conition.

Grizz87

ah ok. i can try that in a bit. decided to go ahead and replace the plugs as well

Grizz87

no change. still cranks, starts, backfires, then dies. Going to try and throw some new plugs in and ill test again.

Edwardgp

We need to get focused on a few things. take plugs out and take a picture of the old ones and put it on here. You need a pressure gauge to check fuel pressure. New pump could be bad. Cap, rotor, wires. Have you pulled the distributor cap, Take a picture of the inside of cap and put it on here.

kestell123

I have never had a 2.8, but if I remember corectlly the 2.8 and TPI had high pressure pumps and the TBI had a lower pressure pump. Is there a chance that got a TBI pump by mistake ? One of the parts store may borrow you a pressure gauge.

Grizz87

well, i took the old plugs out and they had so much carbon on them they was black. placed new ones in it and it starts but is idling rough and has a slow throttle response.

Grizz87

Here is how it's idling and throttle response delay it at the TB

OrangeBird

iTrader: (1)

That stuttering, shuddering while revving means that you have at least one cylinder not firing, for any one of the many reasons that a cylinder (or two) could go dead.....

Grizz87

what are you guys thinking? what should I look at or test???

OrangeBird

iTrader: (1)

Were this mine to diagnose, I'd be checking into which cylinder(s) ain't firing, and then go and determine why. One quick way is to get a cheap infrared heat gauge as I've linked below, and check the exhaust manifolds, right at the cylinder heads to see which cylinder's exhaust is cold (or at least drastically colder than the others).

The standard disclaimer applies; I have no affiliation whatsoever with this link, it's just the first hit on a search of "cheap infrared thermometer"

https://www.ebay.com/itm/39331546614...3ABFBMvpbIhLli

Course, you could also get a good thick and well insulated glove and one by each unplug the spark plug wires and find which cylinder(s) make no difference with the skipping heard in your video. You will find some will cause it to die while at least one will have no reaction, that one is your dead cylinder.

Grizz87

got the inferred therm in today. will probably take a look tomorrow. wonder why one wouldn't be firing. all have new plugs and wires to them.

Grizz87

So it looks like the drivers side is sitting at 230 to 245 deg. Pass side is 100 colder.

Grizz87

What would cause it to do that?

OrangeBird

iTrader: (1)

Hi Grizz87, if one side is 100 degrees colder than the other, that right there is an indication of one (or more) cylinders on that side not firing. Start with the simple stuff, have you checked the fuses "inj 1" and "inj 2" in the fusebox under the dash to ensure that with the key on you have power on both sides of both fuses (use an automotive style test light). If those fuses are good next up will be a "noid light" test of the injector power on the side that's cold. If those don't show and faults next up would be a compression test, to see if all the cylinders actually have enough compression to operate properly.