HusseinHolland

Trans is definitely whiny - but it does have 250K on it. I only have to deal with it for a year or so, after that I'm doing a 350Z drivetrain conversion with the 6 speed. Should be all good after that.

The motor feels strong as it is. One reason I changed the TPS WOT setting was I could see the AFR's get really fat just revving the motor in the driveway. After driving around & coming to work today, about 20min local & highway- the enrichment values seem pretty good under load. I reduced the ECT resistance value a touch as the cruise AFR was a touch rich. Now I have the wideband I do see that the system goes kinda rich right off idle before it levels out, but my old Volvo does much the same. I think I should just put in the 250A breaker, as the first couple revolutions hot cranking with the 125A seemed slightly sluggish before it blew, and less so with the 175a, so perhaps the initial starter draw is high enough to strain the lower amp breaker, and actually induce the slow crank, I dunno. It just seems to crank better now than yesterday. (EDIT - excessive draw was due to faulty rebuilt starter, replaced) I do still need to redo the compression test, as the one I did back in the Spring prior to any valve adjustments had one cylinder well over 10% deviation - 140ish vs. 165 range on the others. Valves were very tight on that one. Overall engine feels pretty darn smooth now it doesn't have a lean condition, for sure.

It has varied. With the nylon fuel tubing on the rail & the stock FPR, It held pressure (close to 30psi) for a day or so. After I took it apart again to look for debris, I switched back to standard (Volvo) 7mm fuel hose for the rail junctions & added the Volvo FPR pod. With this setup, pressure typically drops to around 20psi within 4 hours or so, and overnight is down to no registered pressure.

That's impressive. Since many vehicles have a prime feature (for example, my newer Volvo does), I would still say long term residual rest pressure is not expected.

Got the replacement clutch slave installed, and wheel I had the car jacked up, I took care of the speedo drive inner & outer shaft seals. No pics. I drove the car around, went to Harbor Freight & Home Depot to get some extra dot 3 brake fluid & regular antifreeze. Once the engine is hot then parked, it seems that it cranks slower. When I got home, I shut it down, then realized I didn't pull up far enough in the driveway, so went to restart it. Blew the 125Amp breaker on the starter cable again. I've replaced it with a 175Amp breaker. See how that goes, I'm going to drive it to work tomorrow. It's done much idling in the driveway while I worked the kinks out, so it's definitely. due to have the snot beaten out of it. One drivability issue is that I keep trying to upshift into (non-existent) fifth when I get up around 65-70 when accelerating.

that search actually just brings up my new thread & few presumably related to fuel pressure issues. In any event, I'm likely going to add a momentary contact switch for the time being. As it stands, I only need it for cold starts. Though, having said that, it is likely to change 😞

Fuel pressure will always leak down overnight - I don't know how long it is designed to hold, however I've never seen any 'old' EFI maintain rest pressure for more than a couple hours, if that. I put fuel pressure gauges on all my old cars, so I know from personal observation that even with new fuel pumps, regulators, injectors, etc., long term rest pressure is not part of the design.

Wondering if anyone has done this. I found a thread on HyridZ where the main suggestion was to simply bridge 36/39 w/key on to engage the fuel pump. That appears to be a viable approach, if it comes to that. I need to do this as cold start definitely is impeded by lack of system prime. Hot or warm starts are pretty rapid in terms of cranking time What I was thinking was more along the lines of a timer/delay circuit that would run the pump for 3-5sec when the key is turned, anywhere in ACC or On, so that no additional input is required. I've found a range of timer relay/circuit boards that would possibly do the trick, the issue seems to be making it only run once with the key on signal & not cycle. Couldn't find anything on here, but maybe it's hidden like the AFM/Pot thread. Example:

Painted & reinstalled the dash vent panel today, and put the steering wheel back. No horn pad, as I don't know yet if it's centered exactly. Can't drive it until the new clutch slave arrives & replaces the blown out one.

Did a number of things today. Replaced the ECT with a new Beck Arnley 158-0134 sensor. With that, (ambient temp 50ºF) it started well (after the initial delay with priming), and during warmup. AFR's stayed nice & fat, which was not the case with the old ECT. Once it got closer to normal operating temp, the AFR"s went lean again (16's). So, I put in the 1.1K ohm resistor in series with the ECT. With that, warm AFR's are to rich (13.4-13.7) - so I don't even need 1.1K resistance added to the ECT circuit Pushing very slightly on the AFM lever fattened it up a touch, and smoothed the idle quality So, I lessened the wheel tension by 1 tooth Also adjusted the WOT enrichment TPS settings - the factory position brings it on around 30º opening, so I moved it to closer to 50º Stock adjusted Reset (lowered) the base idle closer to 800rpm, with those changes the AFR was sitting around 14.2 So, I installed the 2.2K potentiometer, wired the 1.1K as well, but decided the 2.2K would give me more range. Since 1.1K puts AFR's at idle around 14.2, I need somewhat under 1K to get the AFR's in the 14.7-14.9 range at idle. Bolts to the left dash frame support Used a 2pole HD090 series connector to join the pot to the ECU. Removed #13 wire from the ECU connector, now that goes into the pot, pot output goes to pin13. Set dial on POT so that 1K ohm is with #1 at 6 o'clock where I can see it Full value (2.2K) puts dial @ just over 5. Unlikely I will ever need to use that end of the scale. Connector tucked up above ECU Warm engine, setting dial to 0 brings AFR's to 14.7-14.9. I'll see how it starts & warms up with that setting tomorrow after work. Still can't drive it to see how it performs on the highway cruising, due to the blown out clutch slave.

I don't have to worry about that - I'm going to do a drivetrain conversion on mine 😄 So, I made a couple of resistor plugins - one 2.2Kohms, the other 1.1K ohms. I'll try them tomorrow & see which runs better. I ordered a couple of POTs, one 1K & the other 2.2K, so depending on which resistor seems to run it better, I'll add the pot so I can tweak the value to make intermediate adjustments. I guess I could just use the 2.2K POT, but I don't know if makes a difference to sensitivity of adjustment.

Thanks to @siteunseen for linking this in the bad AFM thread - bumping it so I don't have to search for it, as I'm going to follow her layout, wiring the pot at the ECU harness just have to recheck the two pins for the sensor - 13 & the ground - looks like 16, 17, 35 & 5 all tie together so I'm not sure it matters which I use Edit - never mind, forgot that this is placed in series, not parallel 🤪

Reading through the whole thing - she gets to the POT input at post 57, after all kinds of futzing with the AFM. Seems like I should leave the AFM alone, and just do the POT. Important details, post#66 Edit - forgot to say - I wish RadioShack still existed - I used to get all my electronic projects odds & ends from them. I guess there just were not enough of us to keep them afloat 😞 EDIT - in post 57, she says: "Anyway, I ran upstairs and grabbed a 5k variable resistor and plugged it into the temp sensor connector. That let me tweak the mix manually. I found that the best mix was achieved in a warm engine with a resistance of 2,550 ohms, while the temp sensor's resistance had dropped to 240 ohms. Thus the mix could be richened about right by adding 2,310 ohms in series with the sensor. Interestingly, I think I remember the value of the previously added resistor being 2.2k, so apparently someone else had been down this road before me. I'm sure at one time it made the engine run very well, and then it got wonky again with age and deterioration." I only ordered a 1K pot, I'm wondering if I should get one that goes at least into the 2K range....

Thanks for the input. It definitely does not feel right at all, you can feel the lean miss, so I don't want to drive it & possibly damage the engine. The POT should be here tomorrow, along with a new ECT. I can run the motor with the Volvo ECT pressed against the t/stat housing & get AFR's in. good range overall, but it doesn't feel 'right', so I'm going to use the correct ECT, check the AFM values & wire in the POT. Hopefully Sunday. Tomorrow is gonna be rain all day. 😞 If I have to, I'll mess with the AFM adjustment. I don't want to spend too much $$$ on components like that, as the whole mess will go away when I do the VQ35DE conversion in a year or so.

Back to the duct work. Had to do this before the steering wheel & glovebox got back in. This is the diagram I found for the AC ducts Driver's side doesn't match the vent I bought listed as being the driver's side, and no way the one I bought will work on the DS. The one I bought listed as pass side is correct for the DS - I found two captive nuts set into the over steering column section of the dash frame. The duct is significantly shorter than the illustration, which threw me off while I was trying to figure out where either vent could fit. pass side ducts. I will have to mod the glovebox, as the AC duct sits into the glovebox area, due to the offset of the non-factory evaporator box width Trying to fit the vertical port on the right - just not going to work so I need to locate another horizontal vent bracket the the vent is supposed to attach to found a pic online of what the right side bracket for the vent should look like

It's way too lean, you can feel the lean miss. To stop this HEI thread from going even further into left field, I started posting in the existing AFM / lean running thread. Thank you for the link - I'll look at adding a POT - that seems like a practical way to make adjustments to the eng. temp ECU input

Adding on here for AFM related concerns - I'm going to go through the EFI resistance tests of the AFM, and then have a go at adjusting the AFM following the AtlanticZ Guide With the engine running at idle, the AFR's are too lean, and gently pushing in on the counter weight definitely evened out the lean condition. I couldn't do that and watch the AFR's, so I don't know how much it actually enriched the base value, however it was a definite improvement. I've ordered a new ECT, so I will swap that out when it gets here. EDIT - also looking at ZedHeads suggestion for adding the temp signal POT (ordered 1K pot)

So, I shouldn't have declared it resolved. 😞 Started fine cold, but as the engine warmed, pretty quickly the AFR's climbed back into the 16 range, so it would seem possible that there is an issue with the ECT. I tried plugging in a Volvo ECT, and with it pressed against the t/stat housing the AFR's were where I wanted them to be - 14.5-7 range at idle, so I swapped it out after the engine cooled. With it installed in the cooling system, the AFR's went even leaner. I'll order a new ECT, just to safe. I'm going to have to investigate a thorough functional test of the AFM also.

Done - had to shorten the 'nut' to 12mm for it snug in place.

I did both openings 1/8" NPT & M5x1 Fixed the running issues! https://youtu.be/pvHhBw-u9Ro First I checked the ECT (cold, 70ºF) - 2160 ohms at the sensor at the ECU : 2180 ohms Normal OP temp 263 ohms. Values within normal range according to Datsun chart (thanks, ZedHead) I could swap it out for a Volvo one - & make it (marginally) fatter when cold.... Might need to do that depending on how the cold starts are now. Anyway, after that I went back to thinking about what could cause the hunting. I realized that when I did the TPS trigger signal, I didn't confirm that the relay I added had diode protection to prevent interference with the stock circuitry. I simply added a diode inline from the TPS to the relay to test the operation. With that in place, the hunting at 2.5K went away. So that aspect was resolved (YAY!) (Thanks also to @Captain Obvious for questioning the off idle interaction . The system still runs lean though. I don't know if all the cleaning out of coking in the TB & clearing other passages has made it leaner. I certainly didn't feel the lean running condition before I started all the mods. I looked at the AFM adjustment, and that made no meaningful difference. Manifold vacuum at idle is good. Regulated Fuel pressure is good While I cogitated on how to address this, I added the AC switch plate and added carpet mat stays So, I decided that instead of futzing with the AFM to try & tweak the AFR's 2 whole points richer, I decided to just raise the regulated pressure to 3bar - using a Volvo regulator of course As you can see form the video above, that brought the AFR's right where they need to be. new regulated fuel pressure under vacuum. Rises to 3bar with vacuum removed. Having confirmed the pressure is consistent & vacuum works I installed a nylon feed line & quick connect in the intake. Old FPR location is bridged with new hose above it. Bay Now I know the system is fully operational, I will revise the return setup, it is overly long - didn't want to cut down the hose that had to connect to the rail return until I knew it would work. With the fueling resolved, I'll switch the HEI module back & see if I can get that aspect resolved

I did deal with the AC switch plate. I realized a rivnut would make the perfect shoulder nut Determined 14mm is the depth I need to seat the T/stat. Cut down a couple rivnuts until I got one that was right. Filed down the OD a touch re-threaded to 10x1, drilled out the cover plate to fit, notched the cap so I can tighten it down. should fit like this

Thanks Z - good idea. I'll do that tomorrow. EDIT - I need to recheck the TPS setting as well - I had that off when I blocked off the BCDD. Need to verify idle/off idle switch point I did remove the rails & hoses, blew out the lines. No sign of debris, but at least I've ruled that out. Also pulled the plugs & checked that. They're not old, and they look pretty even The only other thing I'm wondering about, is the AFM - the cover is not fixed, and I've knocked it off several times. I'm wondering if I somehow messed up the sweep. Can't tell if it's actually making contact with the board. Does seem like a stretch, though. EDIT - looking closely at this pic on the large screen at work, I can see two track marks on the circuit.

I believe it, the issue is that the condition was not present prior to all the recent work, hence the need to revisit the fuel & ignition work I did. I have not touched the AFM, except to rewire the connector, but that was back in the spring & I drove the car many times after that w/o issue. I'll consider making adjustments to the AFM clocking, but not until I've ruled out any issues I may have created.

fitted Charge Lamp

Thanks CptO I have the front lower two secured, along with the 3 countersunk head M5 screws inside the rear tray. I guess I'll make a cross brace to unify the "wings" I don't want them potentially flapping around.