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Renix high altitude CPS experience

Ecomike

NAXJA# 2091
NAXJA Member
Location
MilkyWay Galaxy
Looking for feedback from any one that has tried the Renix high altitude CPS at sea level and otherwise.
 
I've been using high altitude CPS in my 88XJ for quite awhile at 0-800 ft elevation. When they became a little hard to find, I just bought a standard CPS and modified it per Cruiser54's method so the sensor position matched an old high altitude CPS. They work just fine for me.

Best regards,

CJR
 
I used a heat gun and a hammer to advance an obd1 CPS. I noticed that holding a highway cruising speed of 70mph was easier. No changes in mpg or wot acceleration where noticable by me. 87 octane <800feet above sea level.
 
Did they have a working, known to work, or even a connected knock sensor?

Is the knock sensor more or less important using a HA-CPS at sea level?

Not sure if that HA-CPS advances or retards the signal?

Thanks for the feed back folks! Keep em coming.
 
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BTW I scored 2 of them by accident (IIRC, LOL, don't recall if I ordered them or if they sent the wrong ones, or both, LOL) Wells brand made in Mexico, Renix, but they were only about $11 delivered with Amazon Prime.
 
They advance the timing. Put it on and drive it.

That is what I needed to know, confirmation of, thanks. Not advisable since none of my rigs have a known, working, connected knock sensor to tell the ECU to retard the spark timing when it pings....
 
That is what I needed to know, confirmation of, thanks. Not advisable since none of my rigs have a known, working, connected knock sensor to tell the ECU to retard the spark timing when it pings....

Since I cannot cite a source this tidbit is purely anecdotal: If the RENIX ECU does not detect the knock sensor, it will default to the factory preset timing.

In short, you are giving up power, efficiency, and money, every time you fuel up.
 
Since I cannot cite a source this tidbit is purely anecdotal: If the RENIX ECU does not detect the knock sensor, it will default to the factory preset timing.

In short, you are giving up power, efficiency, and money, every time you fuel up.

I don't think so. The High altitude CPS is fooling the eCU as to where TDC is.
 
I think you are both saying two different things, and are both right!! Hypoid is saying not having a working Knock sensor is costing me fuel economy, which 1-2 folks here have claimed repeatedly. (and I think one verified ?) I plan to test that theory out soon on the one running DD rig I can actually test it on this year.

Cruiser's statement is also right, it is fooling the ECU as to where TDC is, and that is why I will not be trying them on my rigs. One is 1500+ miles away, and I have not way to know if the Knock sensor is even connected or working, the other 3 are not currently drive-able, the third does not currently have the knock sensor connected and the CPS is already brand new and working (if ain't broke don't fix it is my motto).

Thanks for the feed back folks!!!

Since I cannot cite a source this tidbit is purely anecdotal: If the RENIX ECU does not detect the knock sensor, it will default to the factory preset timing.

In short, you are giving up power, efficiency, and money, every time you fuel up.

I don't think so. The High altitude CPS is fooling the eCU as to where TDC is.
 
Round to it projects, cost, lack of need for them, never had a working one in 14 years, my daughter's is 2000 miles away making it hard to attach my MT2500 to it, and she has no idea if there is one even one attached to it or if it is even mechanically connected/looking like its still in one piece anymore, and my health and wrenching days are not currently doing well, I am lucky to make it to the bath room in the morning these days when I get up, before I piss myself much less crawl around under jeep and bust my knuckles that I can barley move.

Right now, if I could get around with out screaming in pain, I would be focused on the real problems I have, rust on the damn roof of my Wagoneer, not on fixing something that ain't broke.

Any more questions ? LOL

Why don't they work?
Don't you have a MT2500 to view them?
 
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