EFI 250 Surging

[Anonymous]

Hey Guys,
Got the 250 running in the ute ok, with 1 small problem...
When i'm off the throttle but still moving, ie coasting down from 100->60 or something the ute tends to surge a little, also happens when coasting at about 60 in 4th...
No issues of out gear, motor idles nicly around 600rpm

and ideas ?
the setup is, efi 250, auto computer, single rail, 3.23 rear end. Tied the gearbox input on the ecu low, so it thinks its in gear, tried it floating, and makes no differance other than if the motor is out of gear and you blip the throttle it takes longer to return to idle, maybe it should be held high ?? (havent tried this)

no issues on the throttle other than traction...

ohh, for those interested in bling i got some new wheels...
have a look at http://cam.5u.com

 

[DYNOED250]

Try adjusting the tps slighly.. u may get a bit out of it, it may just be going to idle cirut in the ecu, even try turning base idle up slighly. Has it got the adjustable air bypas screw?

 

[Anonymous]

The TPS doesnt look very adjustable...
I dont know if its got the bypass screw or not, where do i look for it ??

thanks
Cam

 

[wagon]

Hello! Have you checked for airleaks? These systems work well until you get a vacuum leak - try taking off the oil cap whilst the motor is idling - it should run VERY badly, if not stall. If it does not, you have vacuum leaks and someone may have fiddled with the airflow meter settings to richen it up! Remember, ALL air that goes into that motor MUST go through the airflow meter - ANY airleaks will make the engine run lean. Even something as silly as the wrong dipstick! (the efi items have a vacuum seal). I would start looking! Enjoy! (By the way, I am going to dump my eec4 system soon for a megasquirt. There must be more power hiding in there somewhere (maybe economy too).)

 

[Anonymous]

Wrong Dip stick eh ??

well, it just so happens i have a dip stick from a carbed alloy headed 250, as my EFI motor came with out a dip stick !

I'll try the oil cap trick too !

Can one of these seals be fitted to my dip stick ? or should i just get the right one ?


thanks!

Cam

 

[Anonymous]

Ohh, i also meant to say that you've probably got the right idea as my idle tends to vary ! sometimes it'll be happy at 6-700rpm, others ~1000rpm and some times 2000rpm !


Cam

 

[wagon]

Get an efi dipstick - the tube is the same. While I think about it too, your oil cap seal may be hard and not sealing well. These motors are great while they are running! A pain when these niggly things happen.

 

[Vaughano]

<threadhijack>

By the way, I am going to dump my eec4 system soon for a megasquirt.

Let me know if you need any help modifying the assembly code for the microcontroller, I've done a bit of this. (It's very similar to 6502 processor found in the old commodore 64 or apple 2).

</threadhijack>

 

[wagon]

Thanks for the offer mate but I wanted an o2 sensor + no clapped out vane afm + better control than the factory setup can give - it gives me something to do on the weekends that the wife approves of too!

 

[Vaughano]

Thanks for the offer mate but I wanted an o2 sensor + no clapped out vane afm + better control than the factory setup can give - it gives me something to do on the weekends that the wife approves of too!

Agreed! I was referring to the microcontroller in the megasquirt setup.
You might find you have some ideas for reprogramming the control, and its all written in assembler code which aint too easy to follow. : :

My Missus doesn't seem to approve of anything I do on the car, which is probably fair enough since I've spent $1500 on a $200 XF.

 

[wagon]

Agreed again! I spent nearly 10k on our 21year old antique, and my lady reminds me of this often! But, I tell her, it is 'driveable art' and I could have spent my (our??) money on booze, women and gambling. Not that I would anyway. Nothing wrong with old cars anyway! You could buy a newer car and spend 10k on it or an old car for $50 and spend 10k on it. At least with the old one you will be able to find it in the carpark. Plus, if it is an old Ford, you won't be just another bogan in a Dunnydoor (or Silvia, or Hyundai or whatever other junk people insist on driving). I suppose you could still be a bogan in a Ford. BUT a bogan with taste.

 

[Anonymous]

I've decided not to count the money i have spent on my $500 ute !

But i've spent more than $500 many times over !

the new wheels were $1200 alone

and then there is the $400 uhf radio

at least i dont have to worry about the wife complaining about it any more !
She left


Cam

 

[Vaughano]

Yeah, when you look at it $1700 for a car that is basically completely rebuilt (front-end, engine, electrics, carb, exhaust) is pretty good. It should last a while, especially the way I drive.

Of course there's probably a few grands worth of my time, but I've been unemployed for 3 months anyway (just got a job, start tomorrow).

It's satisfying to rebuild something, especially when you don't have a clue to start with! I've always figured if you can pull something apart you should be able to discover how it works, and hopefully put it back together. Any failures can be considered the cost of education.

I've sucked heaps of knowledge out of this forum, many thanks to all.

 

[Anonymous]

Ok, got myself an EFI dipstick over the weekend...
Found the motor does stall with the oil cap taken off...
Only got the dip stick by fluke on saturday night, and had other things to do today, so not sure how much differance it makes...
was also looking at all the hoses connected to the intake manifold and thinking that i should be putting clamps on a lot of them as they seem to have aged a little and are a bit of a sloppy fit....

Will keep everyone posted !!

Cam

 

[wagon]

Ah yes! I should have mention vacuum hoses! Some you can still buy new from ford, and are quite cheap. Check the egr valve and stuff too - it has probably fallen apart - maybe block it up and disconnect the vacuum lines to it (although this is illegal) (don't tell anyone ;} ).

 

[Anonymous]

Damn egr !
One of the bolts to hold the vacuum thing on has been stripped out... need to add some silicone to it and a nut me thinks !!

and get lots of hose clamps


ohh, Dyno250, it does have the bypass screw, assuming your talking about the screw above the butterfly to bleed air thru...


Cam