dcee

Weird problem. (of course)

ECU is an older F9 with a 3-bar AC-Delco MAP sensor (P/N 213-101).

When you hit the gas, instead of the Vacuum decreasing on the Haltech, it increases. I tested the MAP sensor with a MityVac and sure enough... same thing. The higher the vacuum on the MityVac, the lower the vacuum number on the Haltech.

Now the car doesnt even boost (according to the Haltech but it boosts slightly according to the gauge). It *used* to go from low vacuum (~15in-hg) and steadily increase (~29 in-hg) until it would go into boost (1, 2, 3....7psi etc). Now it just keeps increasing in vacuum... all the way up to about 40 in-hg.

Sounds backwards, right? Regardless of what the pressure was said to be (in the engine data area of the HAltech) the maps would indicate that there was an increase in load ( as if it was working properly.)

ANyone ever encounter this problem?

dcee

dcee

Nobody has ever encountered this problem? I guess I will have to change the MAP sensor and see if that takes care of it.

tims

I don't even understand what your problem is. sorry, I don't understand the first post. at idle the engine should make 15-20 in hg(inchs of mercury not psi this is vacuum) when the throttle is opened it should immediately go to 0 psi. if it is a turbo car then boost will built with rpm and load. if you are reving the car in the garage(no load on engine) there will be little to no boost. if vacuum increases when the throttle is opened you probably have a leak. check all hoses for cracks and seperations. if this setup was working and with no other work being done to the car it quit then look for the leak.

dcee

thanks Tims,

When you rev the motor in the garage, instead of the vacuum getting lower, it will go up (lets say from 20 in-hg---> ~40 in-hg). While driving, I have seen the HALTECH read up to 49 in-hg???? I don't even think this is possible. This is what the HALTECH computer is saying the vacuum reading is. The Autometer boost/vacuum gauge in the car reads more normal -> with the throttle closed it reads about 20 in-hg and then goes down as you mash the throttle to about 0psi. It also registers boost when you are driving, like it should. By the way, both are hooked up to the same vacuum port on the engine.

I guess I am just wondering if this sounds like a problem with the MAP sensor (AC-DELCO) or some type of problem or setting in the HALTECH F9.

vosko

iTrader: (4)

my vote goes to bad map sensor or wiring to the map sensor

dcee

I am thinking that too. So if I run the car based on TPS instead of MAP, The car should run decent right?

The thing I do not understand about the F9 software is the way they measure boost/vacuum. I don't know if its because I have old *** software but it goes like this:

When looking at the fuel graph the X-AXIS is labelled pressure(in-hg) and goes from something like 0 to 50? Right there, that is incorrect. It is not linear from the bottom of the load scale(vacuum) to the top of the load scale (boost). WTF?

I am trying to get my friend to buy a new MAP sensor or see if the one he has is under warranty. It does sound like the MAP sensor.

tims

this particular setup has worked correctly in the recent past? or is this a new install with unknown parts? I would get the correct MAP sensor for the Haltech(I know it is a GM type part but be sure it is the correct one). then check that none of the wiring has gotten damaged. if it is a new install check all of the wiring first.

dcee

This is a new install.
The MAP sensor was new when he bought it a couple months ago. AC-DELCO 3 bar. I think it used to register that it was receiving boost . But it always did go up instead of down when revving the motor with no load(ie: in the garage).

tims

sounds like the wrong map sensor. just because it is an AC-Delco part doesn't mean it will work with the Haltech. get the correct map sensor and verify all wiring.

dcee

I agree, It does sound like the wrong part number but I have heard that this AC-DELCO part works.

tims

best to verify with the manufacturer. there are lots of different versions of map sensors.

dcee

yeah but its a map sensor out of an 89 Turbo TransAm. They supposedly work with the Haltech. I have an email into Haltech but didnt get a response. I verified the ACDELCO part number on their site and it is correct.

I am now starting to think that the sensor went bad.

tims

difficult for the sensor to start reading backwards, bad sensor usually reads blank. probably the wrong part. the actual part number has been discussed several times on this board do a search and you should find it. might try one of the local Haltech dealers, they should be happy to sell you the correct sensor.

dcee

I did all the searches and I came to the conclusion that there is many different part numbers from various manufacturers. The one I am using is correct. But the Haltech F9 that I am using seems to be a *very* old version and maybe requires a different sensor. I ran into problems trying to find the software for it because it was that old. I sent another email to Haltech and I am waiting for a response. I will send another one today. Thanks for your input and I'll keep this posted.

vosko

iTrader: (4)

maybe send the F9 back to haltech and have them upgrade it ? save yourself some hassle ?