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I have a 89 touring wagon which i converted to turbo with a vortex 4plug turbo motor.

At the moment i cant get it to run with the turbo vortex ecu, but i can get it to run with the NA touring wagon ecu.

I have this problem where the car surges slightly while cruising, usually when the boost gauge is showing vaccum between -12mmHg and 0mmHg. On boost it runs fine.

I was told that it could be cos the NA ecu is seeing too much air for that throttle opening while crusing, it should only see that much air at WOT.

But talking to Wil, he said that he, as well as others havent had this problem running a turbo motor with a NA ecu.


Could it be my TPS?


Cheers in advance

Anyone?

It also shudders while cold, but his has to be the coolant temp sensor

Suparoo wrote:Anyone?

It also shudders while cold, but his has to be the coolant temp sensor

i dont see why that has to be the coolant temp sensor.

Suparoo wrote:I have a 89 touring wagon which i converted to turbo with a vortex 4plug turbo motor.

At the moment i cant get it to run with the turbo vortex ecu, but i can get it to run with the NA touring wagon ecu.

I have this problem where the car surges slightly while cruising, usually when the boost gauge is showing vaccum between -12mmHg and 0mmHg. On boost it runs fine.

I was told that it could be cos the NA ecu is seeing too much air for that throttle opening while crusing, it should only see that much air at WOT.

But talking to Wil, he said that he, as well as others havent had this problem running a turbo motor with a NA ecu.


Could it be my TPS?


Cheers in advance

Think about what your saying... you listenened to,took on board, and relayed advice here that your ecu is seeing too much air on cruise and not running right ..then it see,s more air on boost and has no problem...its obvious what the problem is....after the amount of tinkering you have fumbled through over the last few years..please refrain from toying with technology which far surpasse,s your grasp of it,s inteligence..people who have problems with there vehicle,s..take on a mental problem which is abnormal to regular thinking,process of diagnosis and analysis become distorted..people who designed these ecu,s did not intend for you to be rednecking around with out installing it correctly... You asked for help and this is the kindest that anyone with common sense can give to an indivdual with limited knowledge on full fuction,s of this ecu....have a good day.... and if anyone take,s offence to this..it only show,s what lie,s ahead for your way of diagnosis..unless you learn before you touch the poisin ivy..........

wtf......?

Issues with cold start are usually related to crappy terminals on the water temp sensor (EA82 EFI) However your surging could be excessive play in the distributor shaft (up and down). This will make the engine hunt at cruise or engine no load conditions. Surging can also be related to dirty fuel filter or dieing fuel pump. As you have a 4 plug ecu its unlikely you have an AFM issue and unless you have had the TPS off or have modified it that is unlikely to be the problem also

If i read in between the lines, we sometimes get contradictory advice in here, and all over the place, because some say you can do this and others say you cannot, based on their own experiences. My old wog mate has the answer for this with cars, "sometimes 2+2= 5" , this was said before electronic engine management came along.

A lot of us experiment due to our inexperience and isolation from those with the experience, so come in here thinking aloud, and sometimes miss a point , even if it is bleeding obvious to others.

what are the revs when it shudders, is it low revs causing the shudder?

is the NA ECU also a four plug or is it only 3. If it is 3 plug what is not connected with the fourth plug ?

and it must be a hotwire AFM not a flapper style ?

Yeah it only shudders under 3k, and in the first 5 minutes of driving.
Its a hotwire/4 plug ecu.

The theory on the engine hunting sounds good. It doesnt die/power/die/power, its more like it cruises normally, then power increases slightly, then drops to normal power again and repeats about once a second to 2 seconds.

Thanks for your help fellas

Shuddering when first off cold and the cruise could be related both to the fuel pump

both ecus are 4 plug are they ?

i thought the shudder may have been at say 500rpm idle

not qualified at all but almost sounds like a controller of something reacting to some signals ??/

Yeah both are 4 plug, but i can only get it to run on the NA one. Im thinking the turbo ecu is toasted.

The shudder is from about 1500-3000rpm (i dont usually drive at less than 2k)

If it was the fuel pump, why would it shudder so bad only when cold and only under 3k?

Suparoo wrote: If it was the fuel pump, why would it shudder so bad only when cold and only under 3k?

Dont really know the answer exactly but a similar thing was happening to another turbo conversion (also was when tank was under 1/2) and the problem was the pump. When it was out of the car it rattled when shaken

Will look into it. I wanna get a Air/fuel ratio gauge too see if the surging is related.

I was also thinking today, could it be my fuel pressure regulator?

Yeah the fuel pressure regulator could be giving you grief, try running it without the vac line connected to see if there is any change.

stab in the dark, detonation? i know in mine in third gear i had detonation under a high load from about 3k up i closed the gab to .9 and problem fixed

doesn't sound like this is the problem though.

I would hear detonation wouldnt i? I know i used to be able to hear it with the carby if i took off and floored it under 2k rpm, sounded like marbles in a can.

I have 1.1 gapped plugs, new leads, i am using 98prem and timing is dead in 20deg. Could too much gap be causing detonation? There is a bigger than factory gap between the rotor and the points inside my dizzy cap, its 18years old, they are a little worn out

Should be no points in your dist.The dist for 4plug is a photo diode setup,early crank sensor style.

the_postie wrote:Should be no points in your dist.The dist for 4plug is a photo diode setup,early crank sensor style.

Yeah i know.
I was refering to the 4 little metal posts in the top of the dizzy cap that connect to the ignition leads on the outside of the cap, i just didnt know what they were called.

the 4 pointed thing under the rotor is a reluctor

regarding your cap woes, what is the D4R number stamped on the outside of the dizzy ?

has anyone mentioned a pin on the ECU (of three plug anyway) is there for switching between turbo/non turbo ? not sure of how it is switched but guess it is either grounded/powered or disconnected for the two options.