Datamaster questions.

[gstacky]

Re: Datamaster questions.

I just read through your thread, I see you are having idle issues, and it just stalls. I also see you have a new distributor. I had a similar problem with dying at idle and it was my distributor. Not saying for sure but it wouldn't hurt to swap one out and try that. There were other members that had the same problem too, all ended up being the distributor. I tried changing all kinds of sensors, replaced all the vacuum lines, nothing else made a difference. Distributor was the answer. Mine ran fine, but as soon as it returned to idle while driving it would stall. When I started it, it would idle fine, but as the idle would come down to the 700 range it would stall.

Anyways, sorry for the long post, but it's worth a shot to try and maybe help your problem.

 

[Damian]

Re: Datamaster questions.

I'll get a log of me driving around with the engine cold up till it gets up to temp. It runs so much better when it's cooler. I'm wondering if I'm having an EGR valve leaking by even though it's new but not actually being used. It's only there for the visual.

Also, is it normal for the engine to (when it's cold) to run rich, and as soon as you put it in any gear, it shoots up to low 15s?

 

[dgoodhue]

Re: Datamaster questions.

A new egr should not leak. You can manually test it when the engine is cold by squeezing diaphragm. Did you connect the egr valve to the solenoid or vacuum source?

 

[Damian]

Re: Datamaster questions.

It's still connected the way it's supposed to be.

 

[Damian]

Re: Datamaster questions.

I didnt check the EGR valve before I started the motor up, but Ill do it later. Ill leave it disconnected. I did, however, run a wire from the alternator to the pink w/black stripe on the ECU and the voltage jumped to 14.4. I revved the engine up to 5k, and it only dropped to 14.3. So, which relay do I need to rewire?

I did just a monitor thing on DM, and Im still seeing my timing drop as soon as I hit the gas.

 

[Damian]

Re: Datamaster questions.

Just checked EGR, that's not it.

 

[Quickstop [UK]]

Re: Datamaster questions.

I'll get a log of me driving around with the engine cold up till it gets up to temp. It runs so much better when it's cooler. I'm wondering if I'm having an EGR valve leaking by even though it's new but not actually being used. It's only there for the visual.

Also, is it normal for the engine to (when it's cold) to run rich, and as soon as you put it in any gear, it shoots up to low 15s?

Did you put the new ignition module in yourself? They hate heat. Sometimes people miss the heat conducting paste that is supposed to go on the bottom. If it's a new dist, maybe the manufacturer forgot.

As far as being rich with a cool engine, that's normal to get the block up to operating temp. I'm not sure of the exact time-frame but unless it is super rich or does it even when the engine is warm, it sounds normal.

 

[Damian]

Re: Datamaster questions.

It was already installed. I'll pull it apart and look at it.

 

[Damian]

Re: Datamaster questions.

I pulled the ignition module out and there was "some" white paste on the under side. I have some fiberglass heat shield roll, so I cut a piece out that fits perfectly underneath. Havent tried it out yet, but thats where Im at.

Im gonna try and rewire the ECU power wire today and do the injector driver mod.

 

[Damian]

Re: Datamaster questions.

No change after all of that. Is it possible that there is something wrong with the O2 sensor and it's not throwing a code?

 

[gstacky]

Re: Datamaster questions.

I'm still suggesting replacing the whole distributor!! Or even borrow one from a known working truck.

 

[dgoodhue]

Re: Datamaster questions.

I would concentrate on cap/rotor/wires/coil/spark plugs(and gap)/coil wiring for tach flutter.

 

[Damian]

Re: Datamaster questions.

I have a brand new distributor in there right now. Plug wires and plugs maybe have 50 miles on them from test driving this thing after the head gasket blew. The plugs have a gap of .30". At idle, it has no tach flutter, it used to until I swapped out the distributor. Thats why I thought it was very odd that it all the sudden had the flutter at higher RPMs.

 

[gstacky]

Re: Datamaster questions.

Bad new parts do exist, especially the way parts are built today. With everything you are describing, it's very similar to my issue this spring which was inside the distributor. Datamaster showed that everything was functioning as it should, it was frustrating to find, I kept switching parts, but at least I had extras laying around. If it were plugs and wires, you would know, so I don't think it's those either.

 

[Damian]

Re: Datamaster questions.

The part that pisses me off, in a bad way too, is that I've changed out so many parts and nothing has come close to fixing this. They have helped in other areas, but not what I was hoping they would fix. Whatever my problem is, it has to do with heat or closed loop. That's why I've been focusing my search with sensors/parts that deal with closed loop. I've even swapped out the ECU with a know working one and no change. I don't know, maybe Dave is right (he is good at doing that), maybe there is something wrong with my chip. I don't think so since it has been slowly getting bad until it blew my head gasket. I haven't touched the O2 sensor but it's also maybe got 5000 miles. I have an AEM wideband, I've read that it can be wired to the ECU and that be used instead of the narrow band. I can always send my chip back to Hood and have him check the chip out and flash it again for me.

If anyone in the LA/OC area has a factory chip I can use, 2 or 3 Bar is fine, I'd buy them lunch if I can use it to see if it does help me out. I've spent so much time trying to figure this out that my neighbor has rebuilt his flathead V8, rebuilt the manual trans, rebuilt the whole front end of his 50s Ford, brakes all brand new, and so on by himself, and my shitbox is still parked in the garage and he is out driving his. It's depressing! Please don't take my frustration as something aimed at you, it's not even close to that. I seriously hate this truck sometimes. It's definitely a love hate relationship.

 

[Quickstop [UK]]

Re: Datamaster questions.

Putting the heat wrap under the ICM is the wrong thing to do. It's a heat sink - stopping the heat by putting insulation under it will make it hotter, not cooler. It can't conduct the heat away. :2cents:

 

[Quickstop [UK]]

Re: Datamaster questions.

Try a different distributor if you can. Saying it's brand new is no guarantee... At least you can rule it out.

 

[fivetodrive]

Re: Datamaster questions.

I would offer you some of my parts but I my truck is not close enough to driving to know off myparts work.

I have some spare chips thatI could burn and send to you though... it's your Sig correct for your build?

 

[randy merritt]

Re: Datamaster questions.

This may be just plain silly, but you mentioned in an earlier post that you had a wideband o2 and was thinking you would have to get your chip reflashed to use it in the ECU. Are you running two o2 sensors, i.e. one for the wideband and one to control closed loop fueling in the ECU? If you only have the wideband and it is not patched into the ECU, the computer has no way to control fuel once the system goes into closed loop (truck warmed up).

Please don't take offense if this question sounds to simple. If you have two o2's, the narrow band sensor may be bad.

 

[Damian]

Re: Datamaster questions.

Try a different distributor if you can. Saying it's brand new is no guarantee... At least you can rule it out.

I have my stock one still, but the gears are trashed. Since Ive blown the head gasket, I have now put in 3 different ICMs which includes the one that came in the new distributor. I put the insulation underneath because I figured heat rises and thats where the ICM gets the heat from. Ill take it out later today.

I would offer you some of my parts but I my truck is not close enough to driving to know off myparts work.

I have some spare chips thatI could burn and send to you though... it's your Sig correct for your build?

Its correct. If you could burn me one with that uses the AEM wideband, Ill gladly pay you for it.

This may be just plain silly, but you mentioned in an earlier post that you had a wideband o2 and was thinking you would have to get your chip reflashed to use it in the ECU. Are you running two o2 sensors, i.e. one for the wideband and one to control closed loop fueling in the ECU? If you only have the wideband and it is not patched into the ECU, the computer has no way to control fuel once the system goes into closed loop (truck warmed up).

Please don't take offense if this question sounds to simple. If you have two o2's, the narrow band sensor may be bad.

Right now I have two separate O2 sensors. The wideband is just being used on its display and the narrow band is on the ECU.