MAP sensor

i got ahold of a code reader. Im throwin codes 14 23 32 and 33. I think the last 3 are all intermitant. But 23 32 and 33 all point to the MAP sensor. so i assume mine is either out, or going out. Question is, what would cause it to go out? Simply time? Vaccume? Im going to check all of my vaccume lines as well. I just dont want to replace it and have it got bad because something else is making it go bad. and just one more question, the MAP is the sensor on the firewall over the passenger side valve cover right?

You originally had a 305 TBI and changed to a crate 350 using the TBI hardware.  How you are getting codes refering to MAP sensor and you want to know its location.  The best i I can think of is you do not have a MAP system on that 89 RS,  They were uaed with TPI engines on 90/92 models. So my guess is you have other peoblems unless someone else tells you have MAP sensor.  Picture may not help you since for a TPI car.


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On GM, also fix the codes in sequence. Code 14 is a coolant circuit issue. Low signal voltage.

Always work from first code to last on OBD 1 systems. Not saying you don't have a MAP problem, your one code checks out for it.

If memory serves me correctly you should, no matter if it is a TBI or TPI have a MAP sensor in the system. With the TPI there is also the MAF(Mass airflow) but the MAP is basically a BARO sensor for altitude adjustments.

This is what you need to look for  if your looking for the MAP

With the Coolant sensor problem. Your going to need to find out with a voltage meter if it is getting any voltage there.

Both the coolant sensor and MAP sensor are cheap,

Looking at your codes, the 23 is for MAT, Manifold Air Temp, which reads incoming air temp for the ECM. Two wire sensor, usually in the air intake for the engine

32 is for a EGR system failure. On the TBI engine, mounted to the passenger rear of the TBI unit. Also have the vacuum sensor for it to worry about.

Finally, your 33...that is for a MAP sensor problem.

Could you clarify what you do have for a setup. I'm a little confused, it's been a long one. You have a 350 cube engine where the 305 was. It has a TBI unit on it? Nothing in the wiring has changed, just a motor swap, correct? It has me confused because I'm looking at Mitchell diagrams and not seeing a factory 305 or 350 TBI setup specific for a 89 Camaro, not saying it didn't happen, just my diagrams say no. I'm starting to wonder if you did a swap and the ECM and Prom don't match up. Has this just begun or has the issue been there since the swap took place?

EDIT again, I see you have a Silverado TBI unit. Does this mean the harness also, and ECM and PROM or did you use the Camaro ECM and prom and do some creative wiring?

yea, thats the part that i was thinking it was willies.

but it does have a 350 swap with the silverado TBI, not sure about the harness, the swap was done by the previous owner, which is why im having such a hard time getting to the root of this problem of mine..

all i wanna do is get this damn thing to pass emissions ONE LAST TIME! i only need it once more since im excluded from the sniffer after september. And thats what my scanner was telling me. I see there is a repair in the vaccume line from the back of the TBI to the MAP. Might try and replace that while im doing the sensor, i found it for 60 bucks at the first place i checked, ill check other places too though. see what i can find.

But im just about as clueless as yall when it comes to what EXACTLY is in there as far as harnesses are concerned. Which sucks, and i wish i could find out wtf is was...
 
ive pretty much had it with this TBI though, soon enough im gona find myself a good TPI on ebay or something. And ill take the time to swap it out that way i know EXACTLY whats in there. Cause a SBC is a SBC. but the intake is so different between cars that it makes it difficult to work on when you dont know what it is... such is my case. Anybody know of where a good TPI is for sale? ill obviously need it all...

anybody? reasonably priced of course..

quote:

ORIGINAL: 350rs

yea, thats the part that i was thinking it was willies.

but it does have a 350 swap with the silverado TBI, not sure about the harness, the swap was done by the previous owner, which is why im having such a hard time getting to the root of this problem of mine..

all i wanna do is get this damn thing to pass emissions ONE LAST TIME! i only need it once more since im excluded from the sniffer after september. And thats what my scanner was telling me. I see there is a repair in the vaccume line from the back of the TBI to the MAP. Might try and replace that while im doing the sensor, i found it for 60 bucks at the first place i checked, ill check other places too though. see what i can find.

But im just about as clueless as yall when it comes to what EXACTLY is in there as far as harnesses are concerned. Which sucks, and i wish i could find out wtf is was...

ive pretty much had it with this TBI though, soon enough im gona find myself a good TPI on ebay or something. And ill take the time to swap it out that way i know EXACTLY whats in there. Cause a SBC is a SBC. but the intake is so different between cars that it makes it difficult to work on when you dont know what it is... such is my case. Anybody know of where a good TPI is for sale? ill obviously need it all...

Since your not sure what the previous owner did do. Get the ECM numbers off the case, and then the four letter prom code that is also on the sticker that is on the ECM case. I'm pretty sure he would have swapped ECMs.....but he might have keeped the TPI ecm. I've got a reference guide for GM's threw the 80's and 90's to tell what they where suppose to be in. Can't figure how it would even work having a TPI for a TBI, the scan data going bonkers? but the codes lead me to think something in the harness was eliminated or put where it shouldn't have been put.

quote:

ORIGINAL: williesrepair

Since your not sure what the previous owner did do. Get the ECM numbers off the case, and then the four letter prom code that is also on the sticker that is on the ECM case. I'm pretty sure he would have swapped ECMs.....but he might have keeped the TPI ecm. I've got a reference guide for GM's threw the 80's and 90's to tell what they where suppose to be in. Can't figure how it would even work having a TPI for a TBI, the scan data going bonkers? but the codes lead me to think something in the harness was eliminated or put where it shouldn't have been put.

I see in 350rs's post that he wants to go TPI. Nothing about it going from TPI to TBI. If his car is an RS it is and was not a TPI. He should have no TPI wiring.
 
350rs
Your getting a MAP code. You have driven the car for a long time and this has not been there since you got it? Check the vacuum line on the MAP sensor. Specialy at the nipple. Stretch the line. It could have cracks but wont show unless its pulled and they spread. Map sensors go bad. Wear and tear. A worn distributer will also set a map code though. But a map is cheaper and easier to change. 

when i brought it in to the shop, they were havin the same troubles i was. they tried to look up the prom number but had NO luck at all. meaning its chipped in some way. It ran absolutly terrible on the way home from work today..  in fact it just up and died on me at red light. Runs really rough, and i know a bad MAP will do that, i think ill just have to bite the bullet and change it. Hopefully that will do something good. I know the egr has been messing with me too. Whats that switch or whatever that has the vacumme line from the front of the TBI called? The line goes from the front of tthe TBI, to that "switch" and then out another line to the EGR itself. Its for vaccume, that i know, but i dont know the name of the part, im thinking that might be bad to. There is very little vaccume at the EGR, but plenty from the TBI is my reasoning.

i found a TPI setup on ebay... killer thing, its a few miles from my house, literally... BUT, its off a 92 transam. ANY problems getting this? Since its gona be a complete swap anyway..
 
heres a link.. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=ADME%3AB%3AAAQ%3AUS%3A1&viewitem=&item=110147596177&rd=1. Lemme know ASAP

That switch is the EGR solenoid. It shuts off the vacuum at idle so you have no EGr function

I would ask the guy if you could pic it up and pay in person if he is that close to you. Look at his feed back. He is new and his pictures are a unit on the car. Not of the actual parts that you will get in a group photo.
Buyer Beware

yea, if he calls i was gona ask him if i could come over and see it in person. If all checks out, ill give him the cash