So...it's about to go to the dealer

[90xj06]

well true but there is nothing to say that i could have failed.

 

[XJING]

I once had a crank position sensor that the tip on it was FUBAR and it was hanging on be a little piece of metal it would idle fine then do all sorts of strange things with my idle, but I dont think thats your problem. I am not leaning toward the MAT idea because of the way RENIX works. I am thinking its the electric side of the IAC. good luck

 

[BIGSLVRXJ]

I once had a crank position sensor that the tip on it was FUBAR and it was hanging on be a little piece of metal it would idle fine then do all sorts of strange things with my idle, but I dont think thats your problem. I am not leaning toward the MAT idea because of the way RENIX works. I am thinking its the electric side of the IAC. good luck

Again not saying I don't have sensors that couldn't have been bad out of the box, but I just replaced the CPS also. I will definitely screw with that IAC tomorrow. It also seems to be doing the "stick" up on start up where it revs to like 1500-2000 rpms and then settles back down. So you may be on to something there. I'll report back after tomorrow.

 

[90xj06]

just a question but does the iac pintel completely go in after it warms up?

 

[90xj06]

what if you where to remove the iac and use a screw driver to simulate the iac?

 

[XJING]

http://www.olypen.com/craigh/idle.htm
When I am all out of guesses I usually look here, might try this guys fix, all his mods and fixes have always worked for me. good luck

 

[BIGSLVRXJ]

just a question but does the iac pintel completely go in after it warms up?

I guess I'm not too sure on that.

what if you where to remove the iac and use a screw driver to simulate the iac?

I don't think that would work because there would be a huge vacuum leak wouldn't there?

 

[XJING]

what if you where to remove the iac and use a screw driver to simulate the iac?

thats pretty funny, have you ever taken apart the IAC, first off you would probably scratch the inside of the run with a screw driver, the IAC is a relativly persision instrument and you cant replicate what it does with a screw driver, thanks for playing....

 

[Mechanic_Dave]

I don't know what your problem might be, but i would gather its something with the idle circut as well. I feel for you, I have had more then my fair share of electrical problems myself. If you still can't figure it out.. megasquirt her. Look it up, lotsa info, support and adds more programability. IE do it yourself FI.
If you want to rule out the injectors though, take them in. I took 4 in last year, had them tested, and one rebuilt. Cost me really minimal (and I am cheap when it comes to spending money on mechanics). Just try to find a local shop that specializes. My only recomendation, don't listen to the shop, replace the o-rings while they are out. It will save you a lot of stress.

 

[BIGSLVRXJ]

If you want to rule out the injectors though, take them in. I took 4 in last year, had them tested, and one rebuilt. Cost me really minimal (and I am cheap when it comes to spending money on mechanics). Just try to find a local shop that specializes. My only recomendation, don't listen to the shop, replace the o-rings while they are out. It will save you a lot of stress.

Yeah I may do that, I remember calling one place about a year ago and they said they can't test them without having them in the vehicle or they'll burn them up or something (which I don't believe) but I think I'll call around some more. Oh and yeah o-rings have already been replaced, it only takes 3 of them leaking at once to finally make me decide I should change the orings out.

 

[letank]

noobie to XJ here, but not to heeps.... i have a 74 wagoneer.... and a 90 wrangler.... looking to increase the family....

I always look for the simplest and cheapest things first.

Good grounds.... battery to engine engine back to frame (or is it the reverse for the XJ). even externally good cables can be internally corroded.

How much voltage is your alternator giving. After a minute, this is when full voltage kicks in. Measure at battery and in circuits that are fed DC voltage.

you mentioned backfiring: usually means timing is off or too much raw gas in the exhaust

let us know

Michel
74 wag
90 wranwran

 

[BIGSLVRXJ]

noobie to XJ here, but not to heeps.... i have a 74 wagoneer.... and a 90 wrangler.... looking to increase the family....

I always look for the simplest and cheapest things first.

Good grounds.... battery to engine engine back to frame (or is it the reverse for the XJ). even externally good cables can be internally corroded.

How much voltage is your alternator giving. After a minute, this is when full voltage kicks in. Measure at battery and in circuits that are fed DC voltage.

you mentioned backfiring: usually means timing is off or too much raw gas in the exhaust

let us know

Michel
74 wag
90 wranwran

My grounds are all spotless. In fact I replaced the ground braid and all battery cables with a custom set of 5-90s 2/0 gauge or whatever and all are clean, so I'm relatively sure that's not it. I'll check the alternator output. Yeah backfiring, that's what I would think too but it's not getting too much gas. I've played with the distributor some just moving it around in the groove that it is in and nothing really changes. At this point I'm just trying to figure out if the low idle and backfire are related or if I have 2 different problems.

 

[BIGSLVRXJ]

Just thought I'd let all you guys know that helped, especially XJING, that is was the IAC motor. It actually wasn't bad but I was using the HO one when I should have been using the Renix one. Dur. Anyway thanks again guys, that saved me some serious cash I'm sure.I don't think I ever would've thought twice about the IAC again.

 

[XJING]

Glad your back up and runnin right.