Please Help Im Dying Here

87danger · Oct 6, 2009

I have been having this problem for awail, my truck is studering, it doesnt matter if cold or not but when you stuff it it runs fine!! im getting bad gas mil.... and its smelling not good!! From the problems my dad seams to think its a eletrical prob.... we have replaced the o2 censor plugs wires cap and rotor tps rebuilt the hole distributer checked the fuel pressure its fine has a farely new fuel pump new fuel filter we put in a new ecu but its used and had a different number but it is very close didnt really change any thing we have run code scan on it and got nothing its killing me we have went threw almost any eletrical problem i think it could b!!!!!!

one of my questions is should i b getting a check engine light when i turn the key in the on pos.... because im not and havent with the old ecu or the new one?

And does any one no why this might be happening???

Any help is good help!!!! :bawling:

IMenriched · Oct 7, 2009

87danger said:
I have been having this problem for awail, my truck is studering, it doesnt matter if cold or not but when you stuff it it runs fine!! im getting bad gas mil.... and its smelling not good!! From the problems my dad seams to think its a eletrical prob.... we have replaced the o2 censor plugs wires cap and rotor tps rebuilt the hole distributer checked the fuel pressure its fine has a farely new fuel pump new fuel filter we put in a new ecu but its used and had a different number but it is very close didnt really change any thing we have run code scan on it and got nothing its killing me we have went threw almost any eletrical problem i think it could b!!!!!!

one of my questions is should i b getting a check engine light when i turn the key in the on pos.... because im not and havent with the old ecu or the new one?

And does any one no why this might be happening???

Any help is good help!!!!

there in all likelihood is no bulb in it or it was never connected from ford.
86 & 87' units rarely trip the cel light on the dash even if the ECM trips/stores a code or codes.

the thing about putting in a new / different ECM... one needs to make sure the ECM is correct for the vintage and style of unit, for example

after 88' the 2.9 didn't have a egr valve and the ECM was designed for that.
so if you replaced the ECM with one from a 88' and it is in a 87' the 88' ECM is not looking for the egr signal. and or, vise versa

also one needs to make sure to get a ECM correct for the type of transmission you have....auto vs manual

hope that helps

holyford86 · Oct 7, 2009

86 and 87 rangers do not have a CEL to turn on. I need specifics here, what is the smell you are smelling? if it smells like it's running rich then pull the vacuum line off of the fuel pressure regulator and see if gas dribbles out, the fact that it seems to run better under heavy throttle seems to point to this. It doesn't matter what year 2.9 computer you have, (unless it's a 1990+ California emissions MAF EEC) It will run the engine if the computer is good, It may run like crap but it will run the engine.

87danger · Nov 24, 2009

Yea we went out and got a brand new ecu but its still doing the same!!! we dont think its a fuel prob cause we ran a pressure check and we think its fine could it be the wire harness?

IMenriched · Nov 24, 2009

87danger said:
Yea we went out and got a brand new ecu but its still doing the same!!! we dont think its a fuel prob cause we ran a pressure check and we think its fine could it be the wire harness?

well... yes, smell has much to do with it. your fuel pressure can be good....but if the fuel presure regulator (FPR) is not performing correctly...it can leak into the vacuum line causing fuel to get sucked into the intake..hence giving you that over fueled smell. the fuel presuure needs to be in the 30-40psi range

the smell can also be coolant being burned off or leaking onto hot surfaces.

or just plan bad gas :dunno:

not to say it can't be electrical ....just that you have covered a lot/most of the main problems already. distributor with the pick-up coil...the TFI , plugs & wires.

if this was electrical yet....double check the connections for "push back" of a pin/pins....chaffed wires....and yes it bares repeating recheck the grounds.

AllanD · Nov 24, 2009

'86-87 Rangers have EGR.

The EGR itself is not the problem however the control system
and feedback to the computer for the EGR system is.

I'm betting that first off you have a vacuum leak.

The "Christmas lines" (the tiny Red & Green vacuum lines that
run from the manifold (vacuum source) to the Control solenoid
(on the passengers side mounting panel) and back to the EGR valve.

Those lines run inside a piece of plastic harness tube and they
often break off inside.

With the line broken you either don't get vacuum supply to the solenoid or he vacuum control "signal" never reaches the valve and thus it doesn't operate when commanded.

But what really makes it worse is that the computer KNOW the EGR isn't working iand the factory programming overreacts (grotesquely so) and generates symptoms similar to yours.

My suggestion? get yourself an '88-92 2.9 non-cali computer and swap it in.
If the problem mostly goes away stick an appropriatly sized Ball Bearing
inside the rubber connector on the end of whichever "Christmas line" is
connected to the manifold. and push the rubber connector back on
(this plugs the leak and leaves the illusion that the system is in place
and operating)

The EGR isn't "Necissary" and was only there by government mandate
that dictated method rather than effect.
when the mandate expired ford dropped the EGR system like a hot rock

'88-92 don't have it.

when EGR finally became "necissary" to meet emissions performance
standards in 1994 ford used a completely different system.

BTW, the early EEC is also programmed to NOT set codes for failure of the HEGO, so your entire problem could be a bad or defective HEGO.

AD

Please Help Im Dying Here

87danger

New Member

IMenriched

New Member

holyford86

Some guy with a problem

87danger

New Member

IMenriched

New Member

AllanD

TRS Technical Staff

Sponsored Ad

Sponsored Ad

Staff online

Members online

Member & Vendor Upgrades

Latest posts

Truck of The Month

Recently Featured

Follow TRS On Instagram

Latest Album Photos

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals