Worked i6 idle and oil pressure issues... Ideas? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

defective · 07-17-2004, 10:18

Ok, i've got a few issues at the moment with my EB II i6 4.0L GLi. I�ll start off by running through the work that�s been done to the car.

Quench head, additional head work, shimmed cam, new roller rockers and oversized valve setup; had a lot of hours put into setting up the rockers and proper gaps. Intake via the sequential bonnet scoop, and flowing out a set of pacemaker tuned equal length headers into a 2 � inch high flow stainless sports cat and 2 � sports exhaust setup, and a set of thematic fans out of an EL. Stage 2 shift kit in the 4 speed auto, hot gapped plugs, still running the original cam, original ECU, original GLi fuel system, original intake manifold, etc.

Right, now the problems.

1. Out of gear idle is ridiculously high. It had been sitting at about 1200 RPM, i�ve managed to knock that down to between 1000 to 1100 RPM now so that it doesn�t go into gear so hard. If I take it down any further then this, or set it up according to the book specifications it will start, idle fine, and stall the moment it goes into gear. I tweaked the idle a little bit higher and placed it into drive, it dipped all the way down and just about stalled but managed to get the idle up again by itself, but the moment its under load (fans come on or you turn the wheels) it will stall so i�ve had to settle for an idle around 1100 RPM.

2. Oil pressure is fine when the car is cold, but as soon as it warms up its way too low. I was using Penrite 15W 60 prior and have done away with that because it was too thick when warm (although dash oil pressure gauge was still reading very low, I have the sports instrument cluster installed with appropriate oil pressure sensor) and have moved to GTX3 10W 50 which seems much better for the car when warm, but still the sensor reads very low, and I do have a slight ticking noise from the front of the car.

3. At revs above 3750 the car makes a vibration noise, it only does this when in gear (ie: it will not do it if the car is in Neutral or Park) and sounds more like something is vibrating against something else, not really an internal noise.

These are the major issues at the moment. Any ideas or suggestions would be appreciated. Due to my hours of work (and excessive amount of it) I have not had time to look at it myself or get it into anyone I would trust to look at it for me, so if someone with some experience with theses issues can save me some time by pointing me in the right direction it would be much appreciated.

Regards,
Aaron.

Rollin · 07-18-2004, 00:32

hmmmm.

why did you play around with the shimming of the lifter if you are still using the stock cam?

have you made sure that all of the sensors are plugged in? if the Throttle Position sensor is unplugged then the car will most likely stall when you crack the throttle open.

how are you setting the idle speed? are you sure there are no vacuume leaks in the system?

did you remove the ISC motor (idle speed control)? if you put them on back to front you get a really high idle...

ELwilldo · 07-18-2004, 04:58

Check the ECU for error codes. One faulty sensor/switch can ruin your idle.

defective · 07-18-2004, 05:19

Well I had some time today to have a look around, made sure everything was plugged in, including the ICS, rigged up a test lamp and ran the cars self diagnostic, and incredibly got an error code on the ICS circuit. Checked the circuit, there was power going to the ICS, and when I put 12v directly through the ICS the actuator functioned, but if I disconnected it whilst the car was running I got no change in idle at all. It turned out that due to the connection using two pins which are split into 4 sections, they had over time squashed together (not the two pins squashed together, but each individual pin squashed together there for changing its diameter) causing it to not make contact with the female connector. A stanley knife soon fixed this and I�ve been able to drop the idle again.

As for the oil pressure I think it�s a sensor issue. I've been able to rectify the tapping issue by using a different type of oil and fixing a few other issues, but the oil pressure gauge is still very low. As the car is a GLi it didn�t come with the sports dash, and when I put it in I was unable to source a sensor out of another EB II, and instead took one from an EA 3.9 CPI. They are a different sensor, and possibly feed back differently as well. The sensor itself was also intermittent when first installed but I have had no time to replace it. So I think given that for how low it says the oil pressure to be it is no making any tapping noises that the sensor is just buggered.

Still haven�t had a chance to chase after the vibration noise, but i've encountered similar noises before and they normally turn out to be a fuel line come loose or something along those lines, will look later this week.

And Rollin, I�ve got no idea why it has been shimmed, the whole setup was done by a mate who�s been doing this all his working life (and he�s a lot older than I am). He got the head for me and did the engine and fitted it and set it all up. Its not running standard valves or rocker gear, and I know he put 10 or so hours into getting all that setup alone as well as some additional work after it had all run in. Don�t ask me why I didn�t have him do a cam setup for me at the time, but ill be looking at getting that done soon. Thanks for the input, appreciated. I hadn�t expected to have the time to look at the car today.

Cheers,
Aaron.

Jaysen · 07-18-2004, 06:11

Just something to note: A funny thing that I noticed after doing my head gasket recently is that my EF showed the same vibration probs as yours has. Whilst I had the head off I took the time to remove all the carbon deposits on the piston crowns and around the valves. Now the car revs cleanly and smoothly out to redline without the vibration that it used to have. I know that this is a controversial issue and one that a lot of people will argue, however it certainly worked for me.

Rollin · 07-20-2004, 03:10

so you are saying that the rocker gear and cam came from a different head, and that you have larger valves..ok, then i suppose fitting different shims could be benificial then...you should have got a reground cam while you were at it but

Grant Porter · 07-20-2004, 03:17

This might be a stupid suggestion, but on my car I had the same noise and i couldn't figure why it only happened when the engine was under load. Turned out it was the casing around the cat had come unstuck and when the motor was under load it twists and so does the cat and made the noise. Took me two bloody late nights to find out what it was.

defective · 07-20-2004, 08:22

Some interesting ideas there; will have to spend tomorrow looking under the car.

Just had the car up against a VS V8 5L, kept up with it neck and neck... Bloody sweet... Took it all the way to 160, when of course my top end started to cut out and pickup was not as great as the 8 up that high and so he started creeping forwards. This was repeated multiple times. Can�t wait to chip, cam and fix up the fuel delivery system. That and the fact that I need to replace plugs and leads tomorrow (screwed a lead up the other night, now it�s missing at low revs). Not bad for an EB II i6.

Grant Porter · 07-20-2004, 20:04

Wak more fuel in her and a performance cam - put it on the dyno. You can advance the ignition timing in the ebs and dial in the vernier cam gear. It will haul arse!!!!!!

Rollin · 07-21-2004, 06:18

no more fuel man, they run rich enough already trust me - i put in a stock I6 fuel pressure reg (250kpa) instead of the standard EB XR6 one (300kpa) and picked up about 13hp!!! from running leaner! these things are way to rich stock.