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Boosted on a budget

oh man. How did the first relay look when it came out? Any corrosion? I'm going to be the bearer of bad news, but I think that your cps is on the fritz. Does the tach bounce when it happens?
 
Checked out the main fused wire going to the ecu? I've seen those get pretty nasty in the fuse and I've even had the wire itself go bad.
 
oh man. How did the first relay look when it came out? Any corrosion? I'm going to be the bearer of bad news, but I think that your cps is on the fritz. Does the tach bounce when it happens?
Relays look great. I don't notice the tachometer bounce. I'll check tomorrow

Oh, and I couldn't find a whole throttle body but I found a blade, it should be there tomorrow.

Oh well. I'll try and make it work.

Checked out the main fused wire going to the ecu? I've seen those get pretty nasty in the fuse and I've even had the wire itself go bad.

My entire car has been required with solid connections so I would be surprised.


I'm hoping it's not the MSD or ignition. Also hope it's not the CPS. How do you test it?
 
I forgot about your rewire. :oops:

When I had a bad cps on my 760 I could wiggle the wire while it was running at get it to sputter. They tach would also bounce around and the car would act like it was in spark cut while I was driving sometimes.
 
Also hope it's not the CPS. How do you test it?

Swap it out, or at least take it out and visually inspect it.

If you got a bunch of metal shavings magnetized to the tip, that'll skew your readings. New aftermarket ones can also crap out pretty quickly...
 
I have a new OEM CPS but I've seen new things gonbad. I watched the tach needle and it never moves or bounces when it cuts out (it happens really fast sometimes so I can't see the needle move but when it does it longer, I will check then)

The fact that the fuel pump relay is clicking tells me something but I'm not sure what.
So we have fuel pump relay clicking, tach needle doesn't move, afr's jump to lean during the hesitation...

I've read so many threads volvo and non volvo but am not seeing anything. I did see something about unplugging the O2 and seeing if it still does it. Maybe I'll try that.
 
If the fuel pump relay is clicking, that kinda sounds like something is shutting off/on and killing the signal to the relay. I found this on the interweeb:

[quote="Volvoclub.co.uk']ECU Fuel Pump Control Circuit Repair.

[Tips from Michael Craig] My 940GL with B230F and LH2.4 suffered from a secondary fuel pump relay supply failure, caused by faulty ECU. This problem apparently required a new ECU - VERY expensive. As I am an electronic engineer by profession, I do not believe there is such a thing as 'beyond repair' -atleast for electronics! After a lot of web searching, I managed to gather a small amount of information about the Bosch ECU. Armed with this and an oscilloscope, I was able to diagnose that the circuit within the ECU that controls the fuel pump relay had failed. Further research led me to believe this was a fairly 'standard' fault, as there are a couple of companies here in the UK who specialise in this particular fault, however the prices quoted for repair are still very high - in the order of ?200. This motivated me to re-design the relay control circuit, the details of which I will share with you!

The pump relay control circuit functions as follows:
• When the ignition is initially switched on, the pump runs for about 1 - 2 seconds, in order to 'prime' the fuel rail. If the engine is not started within that time, the pump must stop. You should be able to hear the pump running, so you can test this function by listening! If the engine is not started and the ignition left on, the pump will not run again (see next).
•When the engine is started, the EZK ignition unit sends a series of pulses to the ECU, the rate of which is proportional to the engine speed. When these pulses start, so must the pump. This is how the pump control logic knows if the engine is either starting, running or stopped.
• When the engine is stopped, the pulses from the EZK cease and the pump also stops. If the engine stops for any other reason, it must be assumed that the EZK will also stop, therefore so will the pump.

The 555 timer IC is operated as a slightly modified 'missing pulse' detector. Pulses from the EZK are used to hold the timing capacitor (22uF) in a discharged state. Should these pulses cease, the timing capacitor will charge through 390k and the timer output will change state, turning off the relay drive transistor BC140. The LED and 2k2 are a visual indication of the output state for testing purposes, and could be omitted. The 1uF capacitor ensures that the timer runs on power up, which gives the initial ignition on pump run. The transistor BC107 is really just a switch, and the zener 6v8 limits any spikes from the EZK.

It is possible to construct the circuit using stripboard about the size of a matchbox, which will fit inside the ECU, making a really neat repair. None of the components are particularly critical - most any transistors could be used, however the pump relay draws about 20mA. (This pump relay is actually part of a double relay - two relays in one case - often referred to as the 'LH Jetronic' relay). MOST IMPORTANT - Always disconnect the car battery before removing any ECU connectors. These ECU's are not well protected, and spikes will kill them.
[/quote]
 
I'll check out the wiring and see how it's looking.

Thanks for the help everyone.
 
Didn't know that was frowned upon. Had a couple times with bad relays or bad relay wiring that led me to keep a jumper in the car for emergency purposes. Only had to use it to test on my 245, but my rat infested stang and my old 242 both received that to get me home.
 
I had a thought.. Would having the wiring for the in tank pump backwards cause these issues? I am unsure if I got one of those mis-wired senders from URO.
I noticed some weird noises coming from the main pump. It didn't stay but it wasn't right...:e-shrug:
 
Well I will check it anyways.


F3842CD3-06C2-460E-89D3-B0E8FA405ACD.jpg
 
Maybe one day! But thanks anyways.

I'm going to create a thread about my hesitation and see if anyone has any more ideas.
 
Ok. I hate this car.

Calling all help. Any help from anyone with Mega/Micro squirt knowledge willing to help.

Im going to rip LH out and replace it. Problem: I have no idea what im doing. I am researching and reading. Hopefully I will find out that I am capable of learning the aspects of tuning. I am not strong in that section. It seems harder to get help these days when you need em so my next adventure is going to be a long rough one.

I really want to thank everyone who has contributed advice and help to me over the past few years. Its been awesome having someone who cares enough to help. From finding a shop rag in the intercooler piping to LH tuning. Thank you all!

No that im done crying, I am going to start my Micro Squirt journey!!
 
Red the megamanual end to end front to back and back to front.

Use microsquirt.

Use batch fire injection

Use a hall effect distributor as your crank trigger

Add provisions for sequentia injection, 60-2 crank trigger, and CAS for when you get more advanced.

Buy a wiring harness from Lord_Athlon

Everything else is easy from there on out.
 
I hope lord Athlon's harnesses are higher quality than the ones DIYAT ship out! :-/

MegaManual is of limited use, it covers a different system to what you'll actually use (you poor bastard).

You want to head to msextra.com and read their docs, because that's what you'll use - without that M$ is near worthless. With it it's just average.

Main tip: Do not be scared of the "tuning EFI" stuff, just be scared of the config options, inconsistencies, etc. Nothing's black magic. Basics to moderate power levels are cake, period. Start off rich and retarded, like your president. Work backward from there. Use fresh plugs. Multiple sets if too rich/retarded :-)
 
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