Hi,
I was under the impression that my irocz had aN electric fuel pump. I just read in the manual that it has a mechanical pump which I can?t find anywhere in the engine bay. I only see this in pic. The manual also say that some cars has ?special type of pump? . Is that what the picture below is?
any help appreciated!

Bracket with the blue in it
also I had an engine swap but No fuel pump swap that I know off.

 

Baro sensor

 

thank you! What’s the function of this?

 

Do you have a computer Controlled carb ?

 

I did but when the engine was swap to Carbureted sbc 350, I was told the computer no longer controlled the carb.

 

If you went to non computer controlled carb and hei with vacuum advance it not needed.
It use to measure pressure outside the engine to help the ecm calculate fueling

 

I see... the hose is hooked up to the manifold vacuum and there is no vacuum advance. It is a holley 670cfm street avenger carb. So, it means it is controlled by ecm? So I should be able to get a code from the obd1?

 

The baro sensor was an "enhancement" to the computer-controlled carb system.

Remember: "vacuum", the best indicator of engine load and driver demand available, is the DIFFERENCE IN pressure between the ambient pressure, and the pressure INSIDE the intake manifold. A MAP sensor (the one that looks basically the same but is over by the brake booster) gives the ECM the pressure INSIDE the manifold, but if it doesn't know the TRUE ambient pressure, it still doesn't know the vacuum; if the ambient pressure varies, the MAP will vary along with it, and confuse the signal. Not a big deal if you stay at sea level and the weather never changes like if you're in San Diego let's say, but if you live in Denver and drive much outside the city, it can be a YUUUUUUJJJJJE factor.

The baro sensor wasn't supposed to have a hose. It belongs exposed to the world at large.

But if you no longer have the computer controls on your car, it's not needed. Nor is the MAP sensor, O2 sensor, coolant temp sensor, knock sensor, etc. etc. etc.

The mechanical fuel pump is on the side of the block, down low, pass side. Has (or had) 2 rubber lines and one steel.



It's round, and bolts to the place that looks like home plate with the 4 small bolts at the bottom right of the side of the block.

 

Thank you. Great info! I live in Dallas TX and is pretty hot year round except 2 months on winter ( not bad either). I am pretty sure a mechanical pump is gone, and my ported vacuum is capped. I tried to get codes today and I got exactly what the manual side about the service engine light I.e. 12 code first with 3 blinks, etc...

do I need to remove that hose attached to the barosensor?

 

why don't you post a pic of your carburetor and distributor so we can be sure of what you now have?

 

you bet and thanks! Both sides of carb taken.

 

You might want to get a vacuum advance distributor.

 

yes, you'll need a different distributor at some point.

right now, none of your car's ECM components are being used, nor are they needed. this includes the BARO, VAC, Knock and coolant temp sensor (the CTS should be in the water neck, or thermostat housing-if it's still there).

you can remove the entire ECM harness and the computer along with the SES bulb in the dash. if you choose to.

The harness comes through the passenger side fender well and enters the engine bay near the blower. it can be pulled out intact along with the ECM above the passenger foot well. shouldn't have to cut anything. cap any vacuum lines at their source. should only be a vac line to the VAC sensor on the drivers side firewall, but someone has hooked one up to the BARO sensor on the passenger side firewall. none of them are doing anything for you.

your existing distributor looks to be the computer controlled one. with no input to the ECM from the carburetor it will be running on the limp home timing advance that is built into the ICM. replace it with a mechanical dist with vacuum advance and you'll see a power and efficiency increase once it's tuned in properly.

 

You need a new distributor NOW... this is the point. I highly recommend one of these. https://performancedistributors.com/...reetstrip-dui/ You probably won't believe how much better your engine will run with a proper ignition timing curve.

As naf says, NONE of the computer-related sensors and whatnot are doing anything at all anymore. The computer cannot control the carb like it did when stock; there's no throttle position sensor so it has no idea where the throttle is; it's just ... a mess ... like that.

As he also said, you can remove the ENTIRE harness, INTACT, without cutting ANYTHING; and put it in a box so that if you ever do need it for whyever, or if you get a chance to sell it, it's all there and not torn up.

The only vacuum lines you will need, are one from the carb to the dist; the PCV; MAYBE the ones to the charcoal canister, depending on how chopped-up that system is; the brake booster; and the one that runs the HVAC system and cruise control. All other ports, holes, etc. in the carb & intake can be plugged.

 

Great info! Thank You so much!

is replacing the distributor a DIY job or a complex job? I am careful to get things done in the car, but i don’t want to start some thing I can’t finish

 

Pretty easy really. Also easy to screw up by being careless. But a very simple DIY job.

When you get it we'll walk you through how to do it with the least pain and grief.

 

Great! I am fixing to place the order for distributor.

 

hi all,
I have received my distributor and getting ready to install it tomorrow. Any hints or word of advice in how to avoid deadly mistakes?

Thanks again!!

 

Set the engine with the timing mark aligned. Pull the dist cap and observe the rotor: should be pointed either toward the rear just slightly to the pass side (#6 firing) or the front slightly to the driver's side (#1 firing). Pull the old one. Note that the shaft will turn as you lift it out: pay close attention to where it ends up as the gear stops turning it. Observe on your new one, the place that the 12V and tach wires hook up to it: that should point almost directly to the driver's side when it's in. Remove the cap, hold the body in that position, rotate the dist to just slightly CCW of where the old one was. Drop it in. It should go all the way down and contact the intake manifold. The rotor should be pointing to the #1 or #6 spark plug tower on the cap, as described above. Put the clamp on and tighten enough to hold it still but not so tight that you can't turn it. Observe the little star wheel teeth down inside there; pull up on the shaft and rotate it CCW as hard as you can with one hand, and with the other, rotate the dist body to where the teeth line up, then rotate it about ½" of its circumference CCW from there. Install the cap. Plug wires should go on the cap in the firing order 18436572 CW, with #1 just to the driver's side from straight ahead. Use dielectric grease on the inside of the boots. Plug it all back in and enjoy.

What dist did you end up getting? How is its curve set up?

 

Thanks! I will follow order. I end up getting AC delco distributor. The one you recommended look quite nice!!!
I am not sure what you mean with “ curve set up”?

 

Oh wow...

I've explained it so many times, I don't feel like typing it again. Books have been written on the subject that barely scratch the surface.

All distributors are NOT the same. A pre-computer (mechanical) distributor changes the ignition timing in all sorts of ways to respond to all sorts of conditions. What we refer to as the "curve" of a distributor is the way the timing changes according to RPM. It's every bit as critical to engine tuning as working on the carburetor. The difference between a junkyard run-of-the-mill distributor out of some random sedan or compact is NOT the same as one for an engine intended to provide excitement or enjoyment.

A "stock" distributor, ESPECIALLY one intended to replace anything from about 71 or newer which of course covers all distributors of this type, is CRIPPLED with regards to "performance", in favor of EMISSIONS. More than likely, what you just bought is going to be alot more like what would have come in grandma's grocery cart, than anything "sporty" or any such.

I could be wrong of course; I don't know everything about everything, and I don't know just exactly what you just bought. However I DO know that whatever Delphi or whatever they call themselves this week puts in a box labelled "AC Delco", is far more likely to be just like some 1975 2-bbl Impala from the deep smogger era, than anything "fun". I hope I'm wrong but I guess what's done is done.

This has NOTHING to do with "hot spark", "multiple spark discharge" (that's a trademark BTW), "high energy", or ANY of that marketing drivel. It's about making the spark occur at the right point in the engine cycle to optimize its output. You CANNOT fix what ails a typical stock distributor with a bunch of "boxes" and such. Just so you know, that's NOT what I'm talking about... I'm NOT telling you to go out and buy a handful of that.

Installation is the same. Results unfortunately may vary.

 

Got it! Learning in the process... I will research it and get answer for you all, so everybody else know for this particular distributor.

 

Hi all,
again thanks for your help. Distributor is in. Car sounds and runs well. Pretty much the position of the distributor stayed the same.

always blessed to come to this forum!